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Compact ZnO (wurtzite) thin films are prepared on four different substrates by (i) spray pyrolysis or (ii) pulsed reactive magnetron sputtering combined with a radio frequency electron cyclotron wave resonance plasma. Films are characterized by AFM, XRD, Kelvin probe, cyclic voltammetry, electrochemical impedance spectroscopy, and UV photoelectrochemistry. Film morphologies, defect concentrations, crystallite size, and orientation provided specific fingerprints for the electronic structure of ZnO close to the conduction band minimum. Fabricated films are referenced, if relevant, to a model system based on a wurtzite single crystal with either Zn-face or O-face termination. Kelvin probe measurements of the ZnO/air interface distinguished effects of annealing and UV excitation, which are attributed to removal of oxygen vacancies close to the surface. In turn, the work function, at the electrochemical interface, specifically addressed the growth protocol of the ZnO electrodes but not the effects of crystallinity and annealing. Finally, high photocurrents of water oxidation are observed exclusively on virgin films. This effect is then discussed in terms of photocorrosion, and work function changes due to UV light. [ABSTRACT FROM AUTHOR]

Ta1−xAlxN thin films with 5, 15, and 40 at.% Al addition were co‐deposited by reactive magnetron sputtering and characterized by Rutherford backscattering spectroscopy (RBS), grazing angle X‐ray diffraction (GAXRD), X‐ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), nanohardness, and oxidation tests. GAXRD and XPS analyses showed, regardless of the % Al added, the non‐existence of ternary nitride Ta1−xAlxN, but always as individual binary nitrides, TaN and AlN. Sample TaAlN_15 obtained the highest hardness and H3/E2 values, possibly due to the AlN grains presence, which were efficient in distorting the TaN lattice. All samples failed oxidation tests at 873 K, showing that the Al addition was not efficient in improving this property for tantalum aluminum nitride thin films. [ABSTRACT FROM AUTHOR]

Titanium nitride (TiN) is a candidate material for several plasmonic applications, and pulsed laser ablation in liquids (PLAL) represents a rapid, scalable, and environmentally friendly approach for the large-scale production of nanomaterials with customized properties. In this work, the nanosecond PLAL process is developed, and we provide a concise understanding of the process parameters, such as the solvent and the laser fluence and pulse wavelength, to the size and structure of the produced TiN nanoparticles (NPs). TiN films of a 0.6 μm thickness developed by direct-current (DC) magnetron sputtering were used as the ablation targets. All laser process parameters lead to the fabrication of spherical NPs, while the laser pulse fluence was used to control the NPs' size. High laser pulse fluence values result in larger TiN NPs (diameter around 42 nm for 5 mJ and 25 nm for 1 mJ), as measured from scanning electron microscopy (SEM). On the other hand, the wavelength of the laser pulse does not affect the mean size of the TiN NPs (24, 26, and 25 nm for 355, 532, and 1064 nm wavelengths, respectively). However, the wavelength plays a vital role in the quality of the produced TiN NPs. Shorter wavelengths result in NPs with fewer defects, as indicated by Raman spectra and XPS analysis. The solvent type also significantly affects the size of the NPs. In aqueous solutions, strong oxidation of the NPs is evident, while organic solvents such as acetone, carbides, and oxides cover the TiN NPs. [ABSTRACT FROM AUTHOR]

Yttrium-doped barium zirconate is a commonly used electrolyte material for Protonic Ceramic Fuel Cells (PCFC) due to its high protonic conductivity and high chemical stability. However, it is also known for its poor sinterability and poor grain boundary conductivity. In this work, in response to these issues, reactive magnetron sputtering was strategically chosen as the electrolyte deposition technique. This method allows the creation of a 4 µm tick electrolyte with a dense columnar microstructure. Notably, this technique is not widely utilized in PCFC fabrication. In this study, a complete cell is elaborated without exceeding a sintering temperature of 1350 °C. Tape casting is used for the anode, and spray coating is used for the cathode. The material of interest is yttrium-doped barium zirconate with the formula BaZr0.8Y0.2O3−δ (BZY). The anode consists of a NiO-BZY cermet, while the cathode is composed of BZY and Ba0.5Sr0.5Co0.8Fe0.2O3−δ (BSFC) in a 50:50 weight ratio. The electrochemical impedance spectroscopy analysis reveals a global polarization resistance of 0.3 Ω cm2, indicating highly efficient interfaces between electrolytes and electrodes. [ABSTRACT FROM AUTHOR]

In this paper, a series of AlN–Al nanocomposite films are prepared by reactive magnetron sputtering. The effects of N 2 flow rate on the microstructure and mechanical properties of the films are studied. The formation and evolution mechanism of the nanocomposite structure are revealed. The results show that with the decrease of N 2 flow rate, the microstructure goes through three stages: pure AlN, amorphous Al surrounded nanocrystalline AlN and AlN nanoparticle reinforced Al matrix composite. Benefiting from the good wettability of Al on AlN ceramics, the film deposited at 6 sccm N 2 flow rate forms a nanocomposite structure of about 8 nm AlN grains wrapped by 1–2 nm amorphous Al. The hardness of the films increases first and then decreases with the decrease of N 2 flow rate, ranging from 4 GPa to 25 GPa. The toughness of the films is analyzed by the ratio of H/E, H3/E2, the normalized plastic depth (δ H) and the morphology of large load indentation. The results show that the toughness of the nanocomposite film obtained at 6 sccm N 2 flow rate is significantly improved while maintaining the hardness equivalent to that of pure AlN film. The improvement in toughness comes from the microcracks initiated in AlN hindered by the surrounding Al phase. [ABSTRACT FROM AUTHOR]

Nowadays, copper nitride (Cu3N) is of great interest as a new solar absorber material, flexible and lightweight thin film solar cells. This material is a metastable semiconductor, nontoxic, composed of earth‐abundant elements, and its band gap energy can be easily tunable in the range 1.4–1.8 eV. For this reason, it has been proposed for many applications in the solar energy conversion field. The main aim of this work is to evaluate the properties of the Cu3N thin films fabricated by reactive radio‐frequency (RF) magnetron sputtering at different RF power values to determine its potential as light absorber. The Cu3N films were fabricated at room temperature from a Cu metallic target at the RF power ranged from 25 to 200 W onto different substrates (silicon and glass). The pure nitrogen flux was set to 20 sccm, and the working pressures were set to 3.5 Pa and 5 Pa. The X‐ray diffraction results showed a transition from (100) to (111) preferred orientations when RF power increased; the atomic force microscopy images revealed a granular morphology, while Fourier transform infrared spectroscopy and Raman spectra exhibited the characteristics peaks related to Cu–N bonds, which became narrower when the RF power increased. Finally, to stablish the suitability of these films as absorber, the band gap energy was calculated from transmission spectra. Highlights: Stable thin films of Cu3N were prepared at room temperature by reactive magnetron sputtering. A transition from (100) to (111) preferred orientation was observed as radio‐frequency (RF) power increased.Fourier transform infrared spectroscopy and Raman revealed the formation of Cu–N chemical bond, improved as RF power increased.The band gap energy values obtained were in the suitable range to use the material as solar absorber. [ABSTRACT FROM AUTHOR]

Lead titanate thin films of pyrochlore phase were deposited using layer-by-layer reactive magnetron sputtering on a heated platinized silicon substrate. It was found that the pyrochlore phase transition to the perovskite phase was initiated at 700 °C, and the properties of the PbTiO3 films could be controlled by changing the annealing environment. The thin films annealed in air and oxygen environments (1.33 Pa) have a tetragonal structure. The highest values of remnant polarization and the coercive field were 38 μC/cm2 and 130 kV/cm, respectively, but the largest dielectric loss was determined for the films annealed in air. The remnant polarization, coercive field and dielectric loss were reduced when the annealing of films was performed using oxygen gas at 1.33 Pa pressure. The films annealed in vacuum showed a rhombohedral (and ferroelectric) structure with the lowest remnant polarization and coercive field values. Such a structure was not observed for lead titanate at room temperature. It was observed that the surface morphology strongly depended on the reaction rate, which was influenced by the oxygen concentration in the environment. [ABSTRACT FROM AUTHOR]

Titanium nitride (TiN) is a candidate material for several plasmonic applications, and pulsed laser ablation in liquids (PLAL) represents a rapid, scalable, and environmentally friendly approach for the large-scale production of nanomaterials with customized properties. In this work, the nanosecond PLAL process is developed, and we provide a concise understanding of the process parameters, such as the solvent and the laser fluence and pulse wavelength, to the size and structure of the produced TiN nanoparticles (NPs). TiN films of a 0.6 μm thickness developed by direct-current (DC) magnetron sputtering were used as the ablation targets. All laser process parameters lead to the fabrication of spherical NPs, while the laser pulse fluence was used to control the NPs’ size. High laser pulse fluence values result in larger TiN NPs (diameter around 42 nm for 5 mJ and 25 nm for 1 mJ), as measured from scanning electron microscopy (SEM). On the other hand, the wavelength of the laser pulse does not affect the mean size of the TiN NPs (24, 26, and 25 nm for 355, 532, and 1064 nm wavelengths, respectively). However, the wavelength plays a vital role in the quality of the produced TiN NPs. Shorter wavelengths result in NPs with fewer defects, as indicated by Raman spectra and XPS analysis. The solvent type also significantly affects the size of the NPs. In aqueous solutions, strong oxidation of the NPs is evident, while organic solvents such as acetone, carbides, and oxides cover the TiN NPs.

Group IV transition metal (III) nitrides (MeN) are plasmonic materials that possess high optical absorption cross-sections and fast electron–phonon coupling that make them attractive in solar energy harvesting. Nanoparticles (NPs) of MeN dispersed in host liquids were predicted to be useful in photothermal energy conversion, although such nanofluids have never been systematically studied, mainly because of the complexity of their preparation. This research introduces reactive magnetron sputtering of Ti, Zr, and Hf targets in Ar/N2 mixtures that can be tailored to produce beams of MeN NPs and load them into vacuum-compatible host liquids of polyethylene glycol, paraffin, and pentaphenyl trimethyl trisiloxane to produce MeN nanofluids in a single process. The NPs are cubic in shape, have a mean size of 10–12 nm, and exhibit a rock salt crystal structure characteristic of Me-(III)-N. The nanofluids based on these NPs reveal a turquoise color, given by a narrow optical transmittance window in the blue-green region and strong absorption at shorter and longer wavelengths caused by interband transitions and localized surface plasmon resonance in MeN NPs. These results open a path toward the synthesis of advanced plasmonic nanofluids without the involvement of aggressive compounds, high temperatures, or multiple chemical steps. [ABSTRACT FROM AUTHOR]

The pursuit of efficient, profitable, and ecofriendly materials has defined solar cell research from its inception to today. Some materials, such as copper nitride (Cu3N), show great promise for promoting sustainable solar technologies. This study employed reactive radio-frequency magnetron sputtering using a pure nitrogen environment to fabricate quality Cu3N thin films to evaluate how both temperature and gas working pressure affect their solar absorption capabilities. Several characterization techniques, including X-ray diffraction (XRD), Rutherford backscattering spectrometry (RBS), Raman spectroscopy, scanning electron microscopy (SEM), nanoindentation, and photothermal deflection spectroscopy (PDS), were used to determine the main properties of the thin films. The results indicated that, at room temperature, it is possible to obtain a material that is close to stoichiometric Cu3N material (Cu/N ratio ≈ 3) with (100) preferred orientation, which was lost as the substrate temperature increases, demonstrating a clear influence of this parameter on the film structure attributed to nitrogen re-emission at higher temperatures. Raman microscopy confirmed the formation of Cu-N bonds within the 628–637 cm−1 range. In addition, the temperature and the working pressure significantly also influence the film hardness and the grain size, affecting the elastic modulus. Finally, the optical properties revealed suitable properties at lower temperatures, including bandgap values, refractive index, and Urbach energy. These findings underscore the potential of Cu3N thin films in solar energy due to their advantageous properties and resilience against defects. This research paves the way for future advancements in efficient and sustainable solar technologies. [ABSTRACT FROM AUTHOR]

The processes of reactive magnetron sputtering of Ti–Al composite targets with varying Al/Ti ratios were studied. Dependences of deposition rate, discharge voltage, elemental composition, and intensity of reference plasma emission lines were determined as functions of the oxygen concentration in the Ar–O2 gas mixture. It was demonstrated that, in reactive sputtering of Ti–Al composite targets, the discharge voltage is determined by the effective ion–electron emission coefficient (IEEC), which depends on the area occupied by the metals on the target, their oxidation states, and the IEEC of the metals and their oxides. The deposition rate of TixAl1 – xOy films both in the metallic and transitional sputtering modes increases proportionally to the fraction of Al in the target, and the relative concentration of the metals in the deposited films depends on the oxygen concentration in the Ar–O2 gas mixture and is determined by the reactivity of the constituent materials in the target. By optical emission spectroscopy (OES), it was shown that the ratio of the atomic concentrations of Al and Ti in the deposited TixAl1 – xOy films uniquely depends on the ratio of the intensities of the aluminum emission line (AlI) and the titanium emission line (TiI) in the plasma. This allows using OES for predicting the metal contents in the films in reactive magnetron sputtering of Ti–Al targets. [ABSTRACT FROM AUTHOR]

Yttrium-doped barium zirconate is a commonly used electrolyte material for Protonic Ceramic Fuel Cells (PCFC) due to its high protonic conductivity and high chemical stability. However, it is also known for its poor sinterability and poor grain boundary conductivity. In this work, in response to these issues, reactive magnetron sputtering was strategically chosen as the electrolyte deposition technique. This method allows the creation of a 4 µm tick electrolyte with a dense columnar microstructure. Notably, this technique is not widely utilized in PCFC fabrication. In this study, a complete cell is elaborated without exceeding a sintering temperature of 1350 °C. Tape casting is used for the anode, and spray coating is used for the cathode. The material of interest is yttrium-doped barium zirconate with the formula BaZr0.8Y0.2O3−δ (BZY). The anode consists of a NiO-BZY cermet, while the cathode is composed of BZY and Ba0.5Sr0.5Co0.8Fe0.2O3−δ (BSFC) in a 50:50 weight ratio. The electrochemical impedance spectroscopy analysis reveals a global polarization resistance of 0.3 Ω cm2, indicating highly efficient interfaces between electrolytes and electrodes.

Amorphous Ta-Zr-Si-B-C and Ta-Zr-Si-B-N coatings were deposited by magnetron sputtering using a ceramic target in Ar + C2H4 and Ar + N2 reaction media. Thermal stability under in situ TEM heating, vacuum annealing and nanoindentation, as well as the effect of heating on structural-phase transformations in coatings and their mechanical characteristics, have been studied. The results showed that the heating of amorphous Ta-Zr-Si-B-C and Ta-Zr-Si-B-N coatings in a TEM column leads to precipitation h-TaSi2 and c-TaC crystalline phases at a temperature of 600 °C and h-Ta5Si3 and c-TaN at a temperature of 1000 °C, respectively. Similar structural-phase transformations were revealed as a result of vacuum annealing. An increase in temperature from 20 to 1000 °C led to a decrease in the hardness of the carbon-containing coating from 21 to 16 GPa as a result of stress relaxation. For the Ta-Zr-Si-B-N coating at a temperature of 1000 °C, an increase in hardness was observed from 18 to 27 GPa, which is associated with the crystallization of the coating, with the formation of a nanocomposite structure with h-Ta5Si3 and c-TaN crystallites of 6–10 nm in size and an a-Si(Zr,B)N amorphous region. [ABSTRACT FROM AUTHOR]

Hafnium oxide thin films have attracted great attention as promising materials for applications in the field of optical thin films and microelectronic devices. In this paper, hafnium oxide thin films were prepared via DC magnetron sputtering deposition on a quartz substrate. The influence of various negative biases on the structure, morphology, and mechanical and optical properties of the obtained films were also evaluated. XRD results indicated that ( 1 ¯ 11 )-oriented thin films with a monoclinic phase could be obtained under the non-bias applied conditions. Increasing the negative bias could refine the grain size and inhibit the grain preferred orientation of the thin films. Moreover, the surface quality and mechanical and optical properties of the films could be improved significantly along with the increase in the negative bias and then deteriorated as the negative bias voltage arrived at −50 V. It is evident that the negative bias is an effective modulation means to modify the microstructural, mechanical, and optical properties of the films. [ABSTRACT FROM AUTHOR]

Zr-Si-N thin films were co-deposited by reactive magnetron sputtering to verify the influence of silicon content (1.6 and 8.0 at. % Si) and substrate temperature (room temperature and heated to 973 K) on structure, morphology, chemical bonds and hardness. GAXRD shows a change in grain orientation from (111) to (200) due substrate heating for sample Zr0.984Si0.016N, furthermore, it was not possible to identify any silicon compounds in all deposited samples. SEM-FEG images show greater roughness and surface clusters for sample Zr0.920Si0.080N due to the heat applied on the substrate, with Si3N4 decomposition, influencing thin film hardness. XPS analyses of Si 2p photoelectronic region shows only Si3N4 presence in all samples, proving, in conjunction with other characterization results, the non-formation of substitutional or interstitial solid solution, regardless of substrate heating or silicon content added to ZrN matrix.

Controlled regeneration processes involving tissue growth using the surface and structure of scaffolds, are actively used in tissue engineering. Reactive magnetron sputtering is a versatile surface modification method of both metal and polymer substrates, as the properties of the formed coatings can be modified in a wide range by changing the process parameters. In magnetron sputtering, the working gas and its composition have an influence on the chemical composition and physical characteristics of the obtained coatings. However, there are no studies addressing the influence of the nitrogen/xenon gas mixture ratio in direct current magnetron sputtering on the deposition rate, physicochemical and in vitro properties of surface-modified biocompatible poly-L-lactic acid scaffolds. In this study, the application of mixtures of nitrogen and xenon in various ratios is demonstrated to modify the surface of non-woven poly-L-lactic acid scaffolds by direct current magnetron sputtering of a titanium target. It has been found that the magnetron sputtering parameters chosen do not negatively influence the morphology of the prepared scaffolds, but increase the hydrophilicity. Moreover, quantitative spectroscopic analysis results indicate that the formed coatings are primarily composed of titanium oxide and titanium oxynitride compounds and is dependent on the gas mixture ratio only to a certain extent. Atomic force microscopy investigations of the roughness of the fibers of the electrospun scaffolds and the thickness of the coatings formed on them show that the considerable variations observed in the intrinsic fiber reliefs are due to the formation of a fine layer on the fiber surfaces. The observed decrease in roughness after plasma modification is due to temperature and radiation effects of the plasma. In vitro experiments with human osteosarcoma cells show that the scaffolds investigated here have no cytotoxic effect on these cells. The cells adhere and proliferate well on each of the surface-modified electrospun scaffolds, with stimulation of cell differentiation in the osteogenic direction. [ABSTRACT FROM AUTHOR]

This paper presents the study of the influence of argon/nitrogen gas concentration ratio in the of reactive magnetron sputtering process on the formation of titanium nitride (TiN) thin films. The addition of 5% nitrogen to the gas mixture is sufficient for the formation of titanium nitride films. It was found that changing the concentration of nitrogen in the reactive gas mixture affects the morphology of the surface, in particular, increasing the concentration of nitrogen leads to an increase in surface roughness of the resulting TiN films. According to the results of Raman spectroscopy, there is a dependence of the ratio of peak areas (TO + LO)/(TA + LA) observed in the regions of 603, 175 and 315 cm-1, respectively, on the N2 concentration. The X-ray Photoelectron Spectroscopy (XPS) analysis results show that increasing the nitrogen content in the reactive gas leads to a decrease in the oxygen concentration in the thin films. The results deepen the understanding of the synthesis of TiN thin films and their potential for the development and improvement of materials for various applications including microelectronics, optics, and coatings. [ABSTRACT FROM AUTHOR]

This work focuses on the evolution of the morphology and structure of La2NiO4 (namely, LNO) coatings deposited by reactive magnetron sputtering (RMS) with subsequent annealing processes. The LNO coatings start to crystallize at 600 °C, and the LNO with K2NiF4 structure was formed at 700 °C. A small amount of La3Ni2O7 appeared in the La2NiO4 coatings at 1100 °C. Interestingly, the LNO coatings realize the transformation from dense to different porous morphologies due to the annealing process. The LNO coating with abundant pores was formed after annealing treatment at 1000 °C for 2 h. This porous morphology can be stably maintained after short-term thermal stability experiments at 750 °C for 120 h. The electrochemical impedance spectroscopy (EIS) measurement of the LNO/YSZ/LNO symmetrical half-cells shows that the LNO cathode coating after annealing at 1000 °C for 2 h exhibits lower polarization resistance (Rpol) and activation energy. [ABSTRACT FROM AUTHOR]

Copper nitride (Cu3N) has gained significant attention recently due to its potential in several scientific and technological applications. This study focuses on using Cu3N as a solar absorber in photovoltaic technology. Cu3N thin films were deposited on glass substrates and silicon wafers via radio-frequency magnetron sputtering at different nitrogen flow ratios with total pressures ranging from 1.0 to 5.0 Pa. The thin films' structural, morphology, and chemical properties were determined using XRD, Raman, AFM, and SEM/EDS techniques. The results revealed that the Cu3N films exhibited a polycrystalline structure, with the preferred orientation varying from 100 to 111 depending on the working pressure employed. Raman spectroscopy confirmed the presence of Cu-N bonds in characteristic peaks observed in the 618–627 cm−1 range, while SEM and AFM images confirmed the presence of uniform and smooth surface morphologies. The optical properties of the films were investigated using UV-VIS-NIR spectroscopy and photothermal deflection spectroscopy (PDS). The obtained band gap, refractive index, and Urbach energy values demonstrated promising optical properties for Cu3N films, indicating their potential as solar absorbers in photovoltaic technology. This study highlights the favourable properties of Cu3N films deposited using the RF sputtering method, paving the way for their implementation in thin-film photovoltaic technologies. These findings contribute to the progress and optimisation of Cu3N-based materials for efficient solar energy conversion. [ABSTRACT FROM AUTHOR]

This work is devoted to investigation of mechanical and tribological properties of carbon nitride (CNx) coatings deposited on the titanium IM125 and steel AISI321 substrates by the method of reactive magnetron sputtering of a graphite target at direct current in a mixture of gases argon/nitrogen. As shown, at pressure р = 0.35 Pa, nitrogen concentration in a mixture of gases С = 42-58%, substrate temperature Tsubstr. = 130°С, the highest values of hardness H = 15-20 GPa, modulus of elasticity E* = 120-132 GPa, normalized hardness H/E* = 0.130-0.152, elastic deformation εes = 4.03-4.6% are obtained, indicating increased ductility and wear resistance of the coating under friction. Wear-resistance testing conducted under dry friction by means of the ball-on-disc and ball-section methods show that high wear resistance is found in CNx coatings with the highest carbon ordering, and it is confirmed by high values of normalized hardness H/E* and εes. Testing in blood plasma of titanium IM125 samples with CNx coating in friction pair with chirulen yields low values of friction coefficient and wear intensity of chirulen equal to 0.079 and 0.65 mm/km, respectively. [ABSTRACT FROM AUTHOR]

The cytocompatibility of titanium oxides (TiO2) and oxynitrides (N-TiO2, TiOxNy) thin films depends heavily on the surface topography. Considering that the initial relief of the substrate and the coating are summed up in the final topography of the surface, it can be expected that the same sputtering modes result in different surface topography if the substrate differs. Here, we investigated the problem by examining 16 groups of samples differing in surface topography; 8 of them were hand-abraded and 8 were machine-polished. Magnetron sputtering was performed in a reaction gas medium with various N2:O2 ratios and bias voltages. Abraded and polished uncoated samples served as controls. The surfaces were studied using atomic force microscopy (AFM). The cytocompatibility of coatings was evaluated in terms of cytotoxicity, adhesion, viability, and NO production. It has been shown that the cytocompatibility of thin films largely depends on the surface nanostructure. Both excessively low and excessively high density of peaks, high and low kurtosis of height distribution (Sku), and low rates of mean summit curvature (Ssc) have a negative effect. Optimal cytocompatibility was demonstrated by abraded surface with a TiOxNy thin film sputtered at N2:O2 = 1:1 and Ub = 0 V. The nanopeaks of this surface had a maximum height, a density of about 0.5 per 1 µm2, Sku from 4 to 5, and an Ssc greater than 0.6. We believe that the excessive sharpness of surface nanostructures formed during magnetron sputtering of TiO2 and N-TiO2 films, especially at a high density of these structures, prevents both adhesion of endothelial cells, and their further proliferation and functioning. This effect is apparently due to damage to the cell membrane. At low height, kurtosis, and peak density, the main factor affecting the cell/surface interface is inefficient cell adhesion. [ABSTRACT FROM AUTHOR]

Reactive magnetron sputtering was used to obtain ZnO films on SiC/porous Si/Si substrates. The silicon carbide film on the surface of porous Si was obtained using chemical substitution of atoms. It has been shown that ZnO films grown at the partial oxygen pressure 0.6 Pa are characterized by a smoother and more uniform surface than coatings grown at the oxygen pressure 0.1 Pa. Being based on the analysis of Raman and photoluminescence spectra, it has been shown that the increase in partial pressure of oxygen leads to the increase in structural disorder of the ZnO crystal lattice, on the one hand, and at the same time to a decrease in the concentration of intrinsic defects, including ionized oxygen vacancies Oi, on the other hand. [ABSTRACT FROM AUTHOR]

Plasmonic nanostructures have attracted tremendous interest due to their special capability to trap light, which is of great significance for many applications such as solar steam generation and desalination, electric power generation, photodetection, sensing, catalysis, cancer therapy, and photoacoustic imaging. However, the noble metal‐based (Au, Ag, Pd) plasmonic nanostructures with expensive costs and limitations to large‐scale fabrication restrict their practical applications. Here, a novel and noble‐metal‐free Al/AlN plasmonic nanostructure fabricated by a reactive magnetron sputtering at the elevated temperature of 200 °C is presented. The unique 3D Al/AlN plasmonic nanostructures show a highly efficient (96.8%) and broadband (full solar spectrum) absorption and a strong photothermal conversion effect on its surface, demonstrating the potential in applications in light‐induced thermal imaging and photo‐thermoelectric power generation. This simple fabrication method and the developed Al/AlN plasmonic nanostructure combine excellent light trapping performance, abundant and low‐cost Al and N elements, good heat localization effect, and scalable fabrication method, suggesting a promising alternative to noble‐metal plasmonic nanostructures for photonic applications. [ABSTRACT FROM AUTHOR]

This work demonstrated the optimization of HiPIMS reactive magnetron sputtering of hafnium oxynitride (HfOxNy) thin films. During the optimization procedure, employing Taguchi orthogonal tables, the parameters of examined dielectric films were explored, utilizing optical methods (spectroscopic ellipsometry and refractometry), electrical characterization (C-V, I-V measurements of MOS structures), and structural investigation (AFM, XRD, XPS). The thermal stability of fabricated HfOxNy layers, up to 800 °C, was also investigated. The presented results demonstrated the correctness of the optimization methodology. The results also demonstrated the significant stability of hafnia-based layers at up to 800 °C. No electrical parameters or surface morphology deteriorations were demonstrated. The structural analysis revealed comparable electrical properties and significantly greater immunity to high-temperature treatment in HfOxNy layers formed using HiPIMS, as compared to those formed using the standard pulsed magnetron sputtering technique. The results presented in this study confirmed that the investigated hafnium oxynitride films, fabricated through the HiPIMS process, could potentially be used as a thermally-stable gate dielectric in self-aligned MOS structures and devices. [ABSTRACT FROM AUTHOR]

This work presents a study on the homogeneity and thermal stability of Al0.7Sc0.3N films sputtered from Al-Sc segmented targets. The films are sputtered on Si substrates to assess their structural properties and on SiO2/Mo-based stacked acoustic mirrors to derive their piezoelectric activity from the frequency response of acoustic resonators. Post-deposition annealing at temperatures up to 700 °C in a vacuum are carried out to test the stability of the Al0.7Sc0.3N films and their suitability to operate at high temperatures. Despite the relatively constant radial composition of the films revealed from RBS measurements, a severe inhomogeneity in the piezoelectric activity is observed across the wafer, with significantly poorer activity in the central zone. RBS combined with NRA analysis shows that the zones of lower piezoelectric activity are likely to show higher surface oxygen adsorption, which is attributed to higher ion bombardment during the deposition process, leading to films with poorer crystalline structures. AFM analysis reveals that the worsening of the material properties in the central area is also accompanied by an increased roughness. XRD analysis also supports this hypothesis, even suggesting the possibility of a ScN non-piezoelectric phase coexisting with the AlScN piezoelectric phase. Thermal treatments do not result in great improvements in terms of piezoelectric activity and crystalline structure. [ABSTRACT FROM AUTHOR]

We report several effects found in reactive bipolar high-power impulse magnetron sputtering (abbreviated as bipolar HiPIMS or BPH) discharges at the substrate level. The role of the negative peak current and the positive pulse voltage, U + , on the deposition flux at the electrically insulating substrate is discussed and the results are compared to conventional DC discharges. In particular, the normalized energy flux, ϕ n , delivered to the substrate is found higher under BPH conditions at U + = +300 V ( φ n = 3.43 × 10 15 eV·nm−3) as compared to the HiPIMS ( φ n = 0.78 × 10 15 eV·nm−3) and DCMS ( φ n = 1.23 × 10 15 eV·nm−3) regimes which is assumed to be provoked by an intensification of the positive ion bombardment. Accordingly, the mean energy and the count of positively charged metal and gaseous ions increase in line with U + as measured by energy-resolved mass spectrometry. Contrariwise, our analysis has shown a significant decrease (≈20 %) of negative oxygen ion count under BPH conditions. [ABSTRACT FROM AUTHOR]

This material can be considered to be an interesting eco-friendly choice to be used in the photovoltaic field. In this work, we present the fabrication of Cu3N thin films by reactive radio-frequency (RF) magnetron sputtering at room temperature, using nitrogen as the process gas. Different RF power values ranged from 25 to 200 W and gas pressures of 3.5 and 5 Pa were tested to determine their impact on the film properties. The morphology and structure were exhaustively examined by Atomic Force Microscopy (AFM), Fourier Transform Infrared (FTIR) and Raman Spectroscopies and X-ray Diffraction (XRD), respectively. The AFM micrographs revealed different morphologies depending on the total pressure used, and rougher surfaces when the films were deposited at the lowest pressure; whereas FTIR and Raman spectra exhibited the characteristics bands related to the Cu-N bonds of Cu3N. Such bands became narrower as the RF power increased. XRD patterns showed the (100) plane as the preferred orientation, that changed to (111) with the RF power, revealing a worsening in structural quality. Finally, the band gap energy was estimated from transmission spectra carried out with a Perkin Elmer 1050 spectrophotometer to evaluate the suitability of Cu3N as a light absorber. The values obtained demonstrated the capability of Cu3N for solar energy conversion applications, indicating a better film performance under the sputtering conditions 5.0 Pa and RF power values ranged from 50 to 100 W. [ABSTRACT FROM AUTHOR]

Deposition of a heteroepitaxial TiHfN film with a growth rate of about 1 μm/h was successfully achieved on a Si (001) substrate at a temperature above 700 °C by direct current magnetron reactive sputtering of a Ti0.6Hf0.4 (in atomic fraction) target with an Ar/N2 gas mixture. Annealing of the as-deposited TiHfN/Si sample at a temperature above 1000 °C using microwave plasma with H2/N2 gas was performed to further improve the TiHfN film's quality. X-ray diffraction results show that the heteroepitaxial TiHfN film on Si exhibits a cube-on-cube relationship as {001}TiHfN//{001}Si and <110>TiHfN//<110>Si. X-ray rocking curve measurements show that the full width at half maximum of (200)TiHfN is 1.36° for the as-deposited TiHfN film, while it is significantly reduced to 0.53° after microwave plasma annealing. The surface morphologies of the as-deposited and annealed TiHfN films are smooth, with a surface roughness of around ~2 nm. Cross-sectional scanning/transmission electron microscopy (S/TEM) shows a reduction in defects in the annealed film, and X-ray photoelectron spectroscopy shows that the film composition remains unchanged. Additionally, S/TEM examinations with atomic resolution illustrate domain matching epitaxy (DME) between TiHfN and Si at the interface. The TiHfN films have good electrical conducting properties with resistivities of 40–45 μΩ·cm. [ABSTRACT FROM AUTHOR]

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The pursuit of efficient, profitable, and ecofriendly materials has defined solar cell research from its inception to today. Some materials, such as copper nitride (Cu3N), show great promise for promoting sustainable solar technologies. This study employed reactive radio-frequency magnetron sputtering using a pure nitrogen environment to fabricate quality Cu3N thin films to evaluate how both temperature and gas working pressure affect their solar absorption capabilities. Several characterization techniques, including X-ray diffraction (XRD), Rutherford backscattering spectrometry (RBS), Raman spectroscopy, scanning electron microscopy (SEM), nanoindentation, and photothermal deflection spectroscopy (PDS), were used to determine the main properties of the thin films. The results indicated that, at room temperature, it is possible to obtain a material that is close to stoichiometric Cu3N material (Cu/N ratio ≈ 3) with (100) preferred orientation, which was lost as the substrate temperature increases, demonstrating a clear influence of this parameter on the film structure attributed to nitrogen re-emission at higher temperatures. Raman microscopy confirmed the formation of Cu-N bonds within the 628–637 cm−1 range. In addition, the temperature and the working pressure significantly also influence the film hardness and the grain size, affecting the elastic modulus. Finally, the optical properties revealed suitable properties at lower temperatures, including bandgap values, refractive index, and Urbach energy. These findings underscore the potential of Cu3N thin films in solar energy due to their advantageous properties and resilience against defects. This research paves the way for future advancements in efficient and sustainable solar technologies.

The processes influencing on the ohmic losses at the border between the reactively magnetron-sputter deposited thin film oxide FTO electrodes and the polymer electrolyte within the cell of an electrochomic device are considered. The function of the registered full ohmic resistance of the device from the total electrical charge collected during the tinting process is established. The influence of the surface area of the device on the contribution to its total ohmic resistance from the resistance of directly the thin-film oxide electrodes is estimated. The assumption about the presence of a random number of ECD charge carriers on the surface of its electrodes at the initial moment of the coloring process, which also contributes to the initial ohmic resistance of the device, was confirmed by independent impedance spectroscopy of the electrolytic layer. [ABSTRACT FROM AUTHOR]

Titanium oxide (TiO2) and oxynitride (N-TiO2) coatings can increase nitinol stents' cytocompatibility with endothelial cells. Methods of TiO2 and N-TiO2 sputtering and cytocompatibility assessments vary significantly among different research groups, making it difficult to compare results. The aim of this work was to develop an integral cytocompatibility index (ICI) and a decision tree algorithm (DTA) using the "EA.hy926 cell/TiO2 or N-TiO2 coating" model and to determine the optimal cytocompatible coating. Magnetron sputtering was performed in a reaction gas medium with various N2:O2 ratios and bias voltages. The samples' morphology was studied by scanning electron microscopy (SEM) and Raman spectroscopy. The cytocompatibility of the coatings was evaluated in terms of their cytotoxicity, adhesion, viability, and NO production. The ICI and DTA were developed to assess the cytocompatibility of the samples. Both algorithms demonstrated the best cytocompatibility for the sample sputtered at Ubias = 0 V and a gas ratio of N2:O2 = 2:1, in which the rutile phase dominated. The DTA provided more detailed information about the cytocompatibility, which depended on the sputtering mode, surface morphology, and crystalline phase. The proposed mathematical models relate the cytocompatibility and the studied physical characteristics. [ABSTRACT FROM AUTHOR]

For decades, partially oxidized hydrides were commonly considered as undesirably contaminated phases and were avoided by scientists. Nevertheless, more recently, it was realized that in some hydrides and oxides, partial substitution of dissimilar H− and O2− anions allows one to obtain unique optical and electrical properties that might have appealing applications in commercial products. It was determined that specific properties of so called oxyhydride materials strongly depend on the used synthesis methods; therefore, there is a great interest in exploring various variants of oxyhydride formation. In the current study, TiHxOy films were deposited by a reactive magnetron sputtering process in Ar-O2-H2 gas mixtures. Color, transparency and crystal phase composition of the films coherently reacted to the Ar:O2:H2 gas ratio. Namely, the rise in partial hydrogen pressure promoted the formation of anatase phase TiO2 structure and darkening of the films. Interestingly, this had only minimal impact on the band gap values, but had a relatively strong negative effect on the photocatalytic activity of the films. The unaccustomed results stressed the difference between the partially reduced TiO2 with a significant amount of oxygen vacancies and synthesized TiHxOy films where some O2− ions are implicitly substituted by H− ions. [ABSTRACT FROM AUTHOR]

AlN is a wide band gap semiconductor that is of growing industrial interest due to its piezoelectric properties, high breakdown voltage and thermal conductivity. Using magnetron sputtering to grow AlN thin films allows for high deposition rates and uniform coverage of large substrates. One can also produce films at low substrate temperatures, which is required for many production processes. However, current models are inadequate in predicting the resulting structure of a thin film when different sputter parameters are varied. In this work, the growth of wurtzite AlN thin films has been carried out on Si(111) substrates using reactive direct current magnetron sputtering. The influence of the processing pressure, magnetron power and N 2 /Ar ratio on the structure of the grown films has been analyzed by investigating crystallinity, residual film stress and surface morphology using X-ray diffraction, profilometry, atomic force microscopy and scanning electron microscopy. In every case, the films were found to exhibit c-axis orientation and tensile stress. It was found that high-quality AlN films can be achieved at an N 2 /Ar ratio of 50% and a low pressure of 0.2 Pa. High magnetron powers (900–1200 W) were necessary for achieving high deposition rates, but they led to larger film stress. [ABSTRACT FROM AUTHOR]

Encoders are widely used for measurements of very small displacements, position and movement speed in metrology instruments, motion systems, and high-precision machining tools, ranging from digital calipers to coordinate measuring machines. Optical scales are the most accurate encoders. Their effectiveness at a near-dew point is limited, thus hydrophilic coatings are being developed for proper instrument functioning at these conditions. Here, we study wetting and structural properties of nitrogen-doped DLC (DLC:N) films, produced with reactive magnetron sputtering (RMS) and inductively coupled plasma (ICP) beam-assisted magnetron sputtering as potential coatings for optical scale technologies. The slope parameter of the DLC:N films increases as the nitrogen content increases. The toughness of DLC:N coatings changes between methods used and is higher for samples when the RMS growth method is used. The DLC:N wetting varies from 33° to 58.8° for different nitrogen content in the DLC films. The increase in atomic nitrogen concentration increases the number of nitrogen-based functional groups and should lessen the hydrophobic influence of the C H group on the contact angle. Furthermore, C O and O H functional groups' promote even higher contact angle decline, hence it seems that introducing oxygen-based groups, encourages hydrophilicity of DLC films. • Reactive magnetron sputtering produces rougher DLC:N films compared to ICP-assisted magnetron sputtering • DLC:N contact angle is smaller than undoped DLC • Lowest contact angle can be achieved with the additional increase in the C-O and O-H functional groups [ABSTRACT FROM AUTHOR]

Amorphous Ta-Zr-Si-B-C and Ta-Zr-Si-B-N coatings were deposited by magnetron sputtering using a ceramic target in Ar + C2H4 and Ar + N2 reaction media. Thermal stability under in situ TEM heating, vacuum annealing and nanoindentation, as well as the effect of heating on structural-phase transformations in coatings and their mechanical characteristics, have been studied. The results showed that the heating of amorphous Ta-Zr-Si-B-C and Ta-Zr-Si-B-N coatings in a TEM column leads to precipitation h-TaSi2 and c-TaC crystalline phases at a temperature of 600 °C and h-Ta5Si3 and c-TaN at a temperature of 1000 °C, respectively. Similar structural-phase transformations were revealed as a result of vacuum annealing. An increase in temperature from 20 to 1000 °C led to a decrease in the hardness of the carbon-containing coating from 21 to 16 GPa as a result of stress relaxation. For the Ta-Zr-Si-B-N coating at a temperature of 1000 °C, an increase in hardness was observed from 18 to 27 GPa, which is associated with the crystallization of the coating, with the formation of a nanocomposite structure with h-Ta5Si3 and c-TaN crystallites of 6–10 nm in size and an a-Si(Zr,B)N amorphous region.

Hafnium oxide thin films have attracted great attention as promising materials for applications in the field of optical thin films and microelectronic devices. In this paper, hafnium oxide thin films were prepared via DC magnetron sputtering deposition on a quartz substrate. The influence of various negative biases on the structure, morphology, and mechanical and optical properties of the obtained films were also evaluated. XRD results indicated that (1¯11)-oriented thin films with a monoclinic phase could be obtained under the non-bias applied conditions. Increasing the negative bias could refine the grain size and inhibit the grain preferred orientation of the thin films. Moreover, the surface quality and mechanical and optical properties of the films could be improved significantly along with the increase in the negative bias and then deteriorated as the negative bias voltage arrived at −50 V. It is evident that the negative bias is an effective modulation means to modify the microstructural, mechanical, and optical properties of the films.

Controlled regeneration processes involving tissue growth using the surface and structure of scaffolds, are actively used in tissue engineering. Reactive magnetron sputtering is a versatile surface modification method of both metal and polymer substrates, as the properties of the formed coatings can be modified in a wide range by changing the process parameters. In magnetron sputtering, the working gas and its composition have an influence on the chemical composition and physical characteristics of the obtained coatings. However, there are no studies addressing the influence of the nitrogen/xenon gas mixture ratio in direct current magnetron sputtering on the deposition rate, physicochemical and in vitro properties of surface-modified biocompatible poly-L-lactic acid scaffolds. In this study, the application of mixtures of nitrogen and xenon in various ratios is demonstrated to modify the surface of non-woven poly-L-lactic acid scaffolds by direct current magnetron sputtering of a titanium target. It has been found that the magnetron sputtering parameters chosen do not negatively influence the morphology of the prepared scaffolds, but increase the hydrophilicity. Moreover, quantitative spectroscopic analysis results indicate that the formed coatings are primarily composed of titanium oxide and titanium oxynitride compounds and is dependent on the gas mixture ratio only to a certain extent. Atomic force microscopy investigations of the roughness of the fibers of the electrospun scaffolds and the thickness of the coatings formed on them show that the considerable variations observed in the intrinsic fiber reliefs are due to the formation of a fine layer on the fiber surfaces. The observed decrease in roughness after plasma modification is due to temperature and radiation effects of the plasma. In vitro experiments with human osteosarcoma cells show that the scaffolds investigated here have no cytotoxic effect on these cells. The cells adhere and proliferate well on each of the surface-modified electrospun scaffolds, with stimulation of cell differentiation in the osteogenic direction.

In this work, we have investigated the potential dual application of TiO2 thin films as a photocatalyst for ammonia degradation, and as a UV light blocking layer in c-Si photovoltaics. For this purpose, we deposited a series of TiO2 thin films on a glass substrate by reactive magnetron sputtering and analysed the influence of the deposition parameters (O2/Ar working gas content and pressure) on the structural, optical and photocatalytic properties. All samples are nanocrystalline anatase TiO2 and have a uniform surface (RMS roughness < 5 nm) in a wide range of magnetron sputtering deposition parameters. They are transparent in the Vis/NIR spectral range and strongly absorb light in the UV range above the optical bandgap energy (3.3 eV), which makes them suitable for the use as UV blocking layers and photocatalysts. The photocatalytic properties were studied in a mini-photocatalytic wind tunnel reactor by examining ammonia degradation. A kinetic study was performed to estimate the reaction rate constants for all samples. The intrinsic reaction rate constant confirmed the crucial role of surface morphology in ammonia decomposition efficiency. [ABSTRACT FROM AUTHOR]

The implementation of a structural material into the hot section of a turbine engine requires the protection against oxidation and water vapour. Since Mo-Si-based alloys do not provide this protection on their own over a long period of exposure time, the necessity for protective coatings becomes inevitable. Rare earth silicates, especially Yb-silicates, are known for their great potential to protect silica against water vapour recession and also for their oxidation protective behaviour due to their low silica reactivity. Reactive pulsed DC co-sputtering was investigated and used to produce a two-layered coating of Yb2Si2O7 and Yb2SiO5. The layers were implemented into a four-layered environmental barrier coating system combined with a bond coat consisting of a graded Mo-Si interlayer and a thin Si top layer intended to form slow-growing silica. The EBCs were tested up to 100 h at 1200 °C and 800 °C isothermally in air on top of three different Mo-Si-based alloys and show promise for oxidation protection. The pesting phenomenon was completely suppressed. [ABSTRACT FROM AUTHOR]

The processes of reactive magnetron sputtering of a V target in Ar/O2 gas mixture are investigated. It was found that when using a pulsed current for sputtering and a pressure in the chamber less than 0.06 Pa, the intensities of the emission lines of vanadium at 437.922 nm, argon at 750.386 nm, and oxygen at 777.417 nm with a change in the oxygen concentration in Ar/O2 gas mixtures (ГO2) have no hysteresis and unambiguously depend on the parameters of the sputtering process, which makes it possible to stabilize the process without using feedback systems. By monitoring the sputtering process by optical emission spectroscopy and depositing films on a rotating substrate of diameter 100 mm, vanadium oxide (VOx) films with nonuniformity thickness less than ±2.4 % and surface resistance less than ±2.5 % were obtained. Studies by transmission line method of the influence of the parameters of the reactive magnetron sputtering and subsequent annealing at O2 pressure of 0.04 Pa on the characteristics of thermoresistive structures based on VOx films showed that when the contacts are deposited without ion cleaning, the current-voltage characteristics (IV) and the dependence of the resistance on the length of resistors R(L) are nonlinear, which indicates the presence of a potential barrier in the contacts. Preliminary ion cleaning can significantly improve the linearity of the IV characteristic. The most linear IV characteristics were obtained for Ti contacts. However, the specific contact resistance of the VOx/Ti contact increases with an increase in the oxidation state of the VOx films and reaches ρc = 0.1 Ohm·m2 at the specific resistance of vanadium oxide ρ = 0.1 Ohm·m. The analysis of the dependences of the temperature coefficient of resistance (TCR) and ρ of VOx films on the annealing temperature showed that, upon annealing, ρ and TCR slightly decrease, i. e. there occurs a partial deoxidation of the films. However, unlike annealing at atmospheric pressure, there are no temperature regions at which a sharp decrease in the resistivity and TCR occurs.

The cytocompatibility of titanium oxides (TiO2) and oxynitrides (N-TiO2, TiOxNy) thin films depends heavily on the surface topography. Considering that the initial relief of the substrate and the coating are summed up in the final topography of the surface, it can be expected that the same sputtering modes result in different surface topography if the substrate differs. Here, we investigated the problem by examining 16 groups of samples differing in surface topography; 8 of them were hand-abraded and 8 were machine-polished. Magnetron sputtering was performed in a reaction gas medium with various N2:O2 ratios and bias voltages. Abraded and polished uncoated samples served as controls. The surfaces were studied using atomic force microscopy (AFM). The cytocompatibility of coatings was evaluated in terms of cytotoxicity, adhesion, viability, and NO production. It has been shown that the cytocompatibility of thin films largely depends on the surface nanostructure. Both excessively low and excessively high density of peaks, high and low kurtosis of height distribution (Sku), and low rates of mean summit curvature (Ssc) have a negative effect. Optimal cytocompatibility was demonstrated by abraded surface with a TiOxNy thin film sputtered at N2:O2 = 1:1 and Ub = 0 V. The nanopeaks of this surface had a maximum height, a density of about 0.5 per 1 µm2, Sku from 4 to 5, and an Ssc greater than 0.6. We believe that the excessive sharpness of surface nanostructures formed during magnetron sputtering of TiO2 and N-TiO2 films, especially at a high density of these structures, prevents both adhesion of endothelial cells, and their further proliferation and functioning. This effect is apparently due to damage to the cell membrane. At low height, kurtosis, and peak density, the main factor affecting the cell/surface interface is inefficient cell adhesion.

A robust hydrophobic Y2O3 coating at high temperatures is important for industrial applications. In this study, Y2O3 thin films on Si substrates were prepared by reactive direct current magnetron sputtering. By changing the deposition power, Y2O3 thin films with different microstructures were obtained in poison mode and metallic mode, respectively. In order to understand the effect of heat treatment on the microstructure and hydrophobicity of Y2O3, the samples were annealed at 400 °C in the air. Compared to metallic mode, no crack was formed on the surface of the Y2O3 film prepared in poison mode. In addition, the water contact angle on the surface of the Y2O3 thin film deposited in poison mode was above 90° before and after annealing at 400 °C. It has been demonstrated that the initial high concentration of physically absorbed oxygen and its slow desorption process in a Y2O3 thin film prepared in poison mode contributes to the hydrophobicity of the thin film at high temperatures. These results can provide insights into the large-scale fabrication of hydrophobic Y2O3 coatings for high-temperature applications. [ABSTRACT FROM AUTHOR]

This paper studies optical properties of Nitrogen-doped a-SiC amorphous, commonly called, silicon carbonitride (SiCN) thin films deposited on polished and textured silicon wafers by reactive RF magnetron sputtering technique. Different samples were made at room temperature by sputtering a silicon carbide (SiC) target in argon and nitrogen mixture environment. The FTIR measurement confirms the presence of Si-C and Si-N bonds. The peaks corresponding to Si-C are 611, 653, 669, 740, 834 cm−1 and the peaks corresponding to Si-N are in the range ~870–950 cm−1. The optical properties were achieved from reflectivity spectra by UV-visible spectroscopy. The refractive index (n < 2.5) and the optical gap (Eg>2.2 eV) of the deposited films depended on the used argon and nitrogen flows. The electrochemical properties of amorphous p-type a-SiC/N thin films on p-Si substrate were investigated as electrodes in H2SO4 aqueous solutions in the dark and under the white light illumination. The SiCN films show a good suitability for the antireflective coating application and can be applied to fabricate high efficient and stable SiCN catalysed n + p-Si photocathode with pyramid surface for PEC CO2 conversion. [ABSTRACT FROM AUTHOR]

In this study, titanium dioxide/copper oxide thin-film solar cells were prepared using the reactive direct-current magnetron sputtering technique. The influence of the deposition time of the top Cu contact layer on the structural and electrical properties of photovoltaic devices was analyzed. The structural and morphological characterization of the TiO2/CuO/Cu2O solar cells was fully studied using X-ray diffraction (XRD), scanning electron microscopy (SEM), and current–voltage (I-V) characteristics. Additionally, using van der Pauw sample geometries, the electrical properties of the titanium dioxide and copper oxide layers were investigated. From the XRD study, solar cells were observed in cubic (Cu2O), monoclinic (CuO), and Ti3O5 phases. In addition, the crystallite size and dislocation density for copper oxide layers were calculated. Basic morphological parameters (thickness, mechanism of growth, and composition of elements) were analyzed via scanning electron microscopy. The thicknesses of the titanium dioxide and copper oxide layers were in the range of 43–55 nm and 806–1223 nm, respectively. Furthermore, the mechanism of growth and the basic composition of the elements of layers were analyzed. The I-V characteristic curve confirms the photovoltaic behavior of two titanium dioxide/copper oxide thin-film structures. The values of short-circuit current density (Jsc) and open-circuit voltage (Voc) of the solar cells were: 4.0 ± 0.8 µA/cm2, 16.0 ± 4.8 mV and 0.43 ± 0.61 µA/cm2, 0.54 ± 0.31 mV, respectively. In addition, the authors presented the values of Isc, Pmax, FF, and Rsh. Finally, the resistivity, carrier concentration, and mobility are reported for selected layers with values reflecting the current literature. [ABSTRACT FROM AUTHOR]

The effect of the condensation temperature and ion-beam treatment alternating with high-frequency magnetron sputtering on the structure and optical properties of thin titanium-oxide films is studied. The films have homogeneous compositions and granular structures; ion-beam treatment changes the grain shape from elongated to rounded. The X-ray diffraction studies show that the phase composition of the films is represented by two modifications of titanium oxide: rutile and anatase. It is found that the increase in the condensation temperature and the intensity of ion-beam treatment influences the film phase composition and their refractive indices. At a low condensation temperature, the dominant phase is rutile; as the condensation temperature increases, the anatase phase forms. An increase in the current density of ion-beam treatment leads to a decrease in the anatase fraction. The decrease in the refractive index of the titanium-oxide films with an increase in the condensation temperature is related to the formation of the anatase phase. Ion-beam treatment also decreases the band-gap width from 3.40 to 3.30 eV. [ABSTRACT FROM AUTHOR]

The aim of this work was to study the effect of the parameters of deposition process and subsequent annealing on the properties of vanadium oxide VOx films deposited by the pulsed reactive magnetron sputtering of a V target in an Ar/O2 gas mixture. The dependences of the structure, phase, temperature coefficient of resistance (TCR), resistivity p, band gap Egof the films on the oxygen concentration in Ar/O2 gas mixture during the deposition ГO2, and the temperature of annealing in an O2 atmosphere were obtained. The films were found to have an amorphous structure after deposition. Crystallization processes are observed at temperatures above 275 °C. In this case, depending on the temperature, polycrystalline films with a monoclinic, cubic or mixed crystal lattice are formed and a transition occurs from the intermediate oxide V4O9 to the mixed phase VO2/VOx/V2O5 and then to the higher oxide V2O5. The character of changes in p, TCR and Egof films coming from the change in the annealing temperature is complex and largely determined by ГO2. It was established that with the view of using VOx films as thermosensitive layers, the following conditions of deposition and annealing would be preferable: films deposited at the oxygen concentration 25 % in Ar/O2 gas mixture and annealed at a temperature of 250–275 °C in an O2 atmosphere for 10 min. Under these conditions VOx films with the following properties were obtained: p= (1.0 – 3.0).10-2 Ohm.m, TCR = 2.05 %/°C, and Eg= 3.76–3.78 eV.

[Display omitted] • Magnetron-sputtered DLC:Cu films effectively release Cu compounds in aqueous media. • Oxygen plasma etching oxidises the Cu and prolongs the metal compound release. • The DLC matrix remains intact despite the different plasma and immersion exposures. • Effective against corona and herpes viruses and E.coli and E.faecalis bacteria. • The Cu release in aqueous media defines the virucidal efficacy of the films. Copper compound-rich films and coatings are effective against widespread viruses and bacteria. Even though the killing mechanisms are still debated, it is agreed that the metal ion, nanoparticle release, and surface effects are of paramount importance to the antiviral and antibacterial efficacy of the surfaces. In this work we have investigated the behavior of the reactive magnetron sputtered nanocomposite diamond-like carbon thin films with copper nanoparticles (DLC:Cu). The films were etched employing oxygen plasma and/or exposed to ultra-pure water, aiming to investigate the differences of the Cu release in the medium and changes in film morphology. The presence of metallic copper and Cu 2 O phases was confirmed by multiple analytical methods. Pristine films were more effective in the Cu release reaching up to 1.3 mg/L/cm2 concentration. Plasma processing resulted in the oxidation of the films which released less Cu, but after exposure to water, their average roughness increased more, up to 5.5 nm. Pristine and O 2 plasma processed DLC:Cu films were effective against both model coronavirus and herpesvirus after 1-hour contact time and reached virus reductions of up to 2.23 and 1.63 log 10 , respectively. Pristine DLC:Cu films were more effective than plasma-processed ones against herpesvirus, while less expressed difference was found for coronavirus. The virucidal efficacy over up to 24 h exposures in the aqueous medium was validated. A bactericidal study confirmed that pristine DLC:Cu films were effective against gram-negative E. coli and gram-positive E. faecalis bacteria. After 3 h, 100 % antibacterial efficiency (ABE) was obtained for E. coli and 99.97 % for E. faecalis. After 8 h and longer exposures, 100 % ABE was reached. The half-life inactivation of viruses was 8.10–11.08 min and for E. faecalis 15.1–72.2 min. [ABSTRACT FROM AUTHOR]

[Display omitted] • Thin films were manufactured using magnetron sputtering with own-invented two-element Zn-Al mosaic target. • The change of Pc/Pe ratio led to the change of the sputtering mode influencing AZO parameters. • Electrical, optical and structural properties were discussed vs. sputtering power and oxygen partial pressure. • The change of the partial pressure of oxygen in the deposition chamber affects selected parameters of the prepared coatings. • Resistivity of 1.02·10-3 Ωcm, transparency of 83 % and free electrons concentration of 6·1020 cm−3 were obtained. This paper presents the results of electrical, optical and structural properties, along with studies of the surface morphology and cross sections of aluminium-zinc oxide (AZO) thin films. The thin films were fabricated by reactive magnetron sputtering using the two-element Zn-Al disk. The properties of the thin films prepared using different sputtering power densities and different oxygen partial pressures in the working chamber were discussed. To control the partial pressure of oxygen, a characteristic parameter of the magnetron power supply, called the circulating power, was used. The best properties of prepared AZO thin film as a transparent oxide conducting thin film were found for the film prepared using the ratio of circulating to effective power equal to 0.5. For that thin film, the electron concentration of about 6·1020 and the band gap properties (bandgap width equal to 3.14 eV, work function equal to 3.75 eV) were determined. [ABSTRACT FROM AUTHOR]