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Aqueous zinc-air battery (ZAB) has attractive features as the potential energy storage system such as high safety, low cost and good environmental compatibility. However, the issue of dendrite growth on zinc metal anodes has seriously hindered the development of ZAB. Herein, the N-doped carbon cloth (NC) prepared via magnetron sputtering is explored as the substrate to induce the uniform nucleation of zinc metal and suppress dendrite growth. Results show that the introduction of heteroatoms accelerates the migration and deposition kinetics of Zn2+ by boosting the desolvation process of Zn2+, eventually reducing the nucleation overpotential. Besides, theoretical calculation results confirm the zincophilicity of N-containing functional group (such as pyridine N and pyrrole N), which can guide the nucleation and growth of zinc uniformly on the electrode surface by both promoting the redistribution of Zn2+ in the vicinity of the surface and enhancing its interaction with zinc atoms. As a result, the half-cell assembled with magnetron sputtered carbon cloth achieves a high zinc stripping/plating coulombic efficiency of 98.8% and long-term stability of over 500 cycles at 0.2 mA cm-2. And the Coulombic efficiency reached about 99.5% at the 10th cycle and maintained for more than 210 cycles at a high current density of 5.0 mA cm-2. The assembled symmetrical battery can deliver 220 plating/stripping cycles with ultra-low voltage hysteresis of only 11 mV. In addition, the assembled zinc-air full battery with NC-Zn anode delivers a high special capacity of about 429 mAh gZn-1 and a long life of over 430 cycles. The effectiveness of surface functionalization in promoting the transfer and deposition kinetics of Zn2+ presented in this work shows enlightening significance in the development of metal anodes in aqueous electrolytes.

Efficient and cheap oxygen evolution reaction (OER) catalysts play an important role in electrochemical energy storage and conversion devices. Transition metal nitrides (TMNs) show excellent OER performance mainly because of their unique electronic structure and high electrical conductivity. In this paper, we report a systematic study in order to explore the relationship between nitrogen deficiency and the OER activity of well-defined Co4N1-x (x > 0) thin film electrodes prepared by magnetron sputtering. The nitrogen deficiency is regulated by changing the Ar-N2 flow ratio and annealing at high temperatures. We find that by decreasing nitrogen content, the surface of Co4N1-x film is more prone to be oxidized with forming a surface Co N O layer. The electrochemical measurements imply that the OER activity can be improved by introducing nitrogen deficiency. The above results could be ascribed to better bulk electrical conductivity and a higher surface ratio of Co3+ in more nitrogen-deficient electrocatalysts. These results possibly provide a new and facile route to promote the OER activity by tuning the nitrogen deficiency in TMNs.

In this study, influence of magnetron sputtering on indium gallium zinc oxide (IGZO) ceramic target was studied to improve its performance and utilization. Results indicated that state of the target such as target grain uniformity, micro defects, C element pollution, and secondary phase showed significant influence on magnetron sputtering process. Atoms located in small grains were easily bombarded out of IGZO target, and grains with slow sputtering rate protruded from target surface. Porous microstructure of IGZO ceramic created abnormal electric field of the target during sputtering, resulting in the poisoning of target. Moreover, more indium atoms were sputtered from the target, and the proportion of In after sputtering decreased by 0.62–0.97%. The difference in sputtering rates between secondary phase and main phase led to the formation of IGZO cladding layer with poor conductivity under the combined action of sputtering and re-sputtering. In sum, these findings may provide strong guidance for further improvement and performance enhancement of IGZO sputtering target.

Photocatalytic processes are promising and ecofriendly approaches to degrade organic pollutants in water. However, the rapid bulk and surface recombination of photogenerated electron-hole (e-h) pairs is the main impediment to the application of photocatalysts. In this paper, TiO2/CuO nanofilms were fabricated and optimized by doping TiO2 with Cr via reaction magnetron sputtering. The morphology, crystalline phase, surface chemical composition, and optical features of the nanofilms were investigated via SEM, XRD, Raman spectroscopy, AFM, XPS, and UV–vis spectroscopy. The experimental results showed that Cr modification led to the production of TiO2 crystals with an increased surface area of the {0 0 1} facet and more surface oxygen vacancies (OVs). Cr-doped TiO2/CuO showed superior photocatalytic activity, degrading 94.1% of rhodamine B (RhB) over 120 min. Furthermore, the Cr-doped TiO2/CuO nanofilm maintained good photocatalytic performance after four cycles of photocatalytic degradation without obvious changes in the morphology or crystal structure. Capture experiments demonstrated that superoxide anion radicals were the main active substance, and a possible mechanism of the photodegradation reaction was proposed.

This study aims at investigating the effect of the substrate material on growth mechanism and also microstructure of Ta2O5 thin films. For this purpose, atomic force microscopy, scanning electron microscopy, and interferometry analyses were implemented to reveal the influence of silicon wafer and amorphous BK7 glass substrates on the nucleation and growth mechanisms of Ta2O5 thin films deposited via the radio frequency magnetron sputtering technique. Results indicated that those films with finer morphologies had relatively higher nucleation densities. Compared with BK7 glass substrate, crystals formed on the silicon wafer were shown to be finer and had lower mean areas in more nucleation sites. Moreover, optical properties and morphological characteristics of the films on the silicon substrates had much more endurance after the annealing treatment. It was observed that shift in the transmission spectra of the deposited films after the treatment was insignificant, implying high packing density of the films. However, a 6-nm shift in the transmission spectra indicated low density and high porosity of the films. Finally, atomic force microscopy analysis along with the light scattering measurements confirmed the formation of a low-roughness film on the silicon wafer substrates.

Thin Fe19Ni81 films were deposited by magnetron sputtering technique onto cyclo olefin (COC) flexible polymer substrates. COC/FeNi(15 nm), COC/FeNi(23 nm), COC/FeNi(25 nm) and COC/FeNi(84 nm) composites were obtained and studied using structural, magnetic and microwave measurements. COC/FeNi(84 nm) composite, which still had certain transparency insured a complete protection with respect to the component of microwave signal polarized along the gunn diode axis (frequency of 10.52 GHz). Even most thin (15 nm) FeNi film was almost as effective as 84 nm film but having much higher transparency acceptable for microfluidic devices. Obtained results indicate that fabricated flexible composites can be used as effective shielding materials in complex multipurpose devices.

Beta-gallium oxide (β-Ga2O3) thin films were prepared on a MgO (100) substrate under different oxygen flow ratios via magnetron sputtering. X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), and UV–visible near-infrared (UV–vis–NIR) analyses were conducted to study how the oxygen flow ratio affected the crystalline quality and the surface topography of the films. Microstructure analysis revealed a clear out-of-plane orientation of β-Ga2O3 (100) || MgO (100). The film deposited under an oxygen flow ratio of 1% presented the optimal single-crystalline structure, while excess oxygen was confirmed to negatively impact the crystallization characteristics of the films. SEM measurements indicated that the increase in the oxygen flow ratio reduced the grain size and RMS roughness. The average transmittance of the β-Ga2O3 films in the visible range exceeded 83%, with a broad luminescence band exhibited at approximately 485 nm in the photoluminescence (PL) spectra.

One-dimensional ZnO exhibits high polarization but is considered to be non-ferroelectric. Here, we show ferroelectricity in carbon-doped ZnO nanocolumnars deposited using one-step DC-unbalanced magnetron sputtering. Doping carbon effectively increases its lattice strain and turns the ZnO nanocolumnars into a ferroelectric material. The existence of a reversible permanent electric dipole is found from the P–E hysteresis loop of the carbon-doped ZnO nanocolumnars, where the highest coercivity (11.1 kV/cm) originated from zinc vacancies and remnant polarization (4.7 μC/cm2) originated from oxygen vacancies. Moreover, the presence of carbon modified the optical bandgap of the system. Supporting the experimental results, the first-principle calculation shows that the increment of C concentration decreases bandgap contributed by C 2p. Furthermore, the existence of ferroelectricity in ZnO has the potential to bring out the multiferroic properties for developing next-generation ZnO-based storage devices.

SiCN ceramics show large potential in high temperature pressure sensors with excellent stability up to 1000 °C, as it is changeling for the most of the existing pressure sensors to work stably at a temperature above 600 °C. However, bulk SiCN ceramics are not compatible to microelectronic processing and exhibit slow response due to viscoelasticity, it is necessary to propose alternative method to prepare SiCN functional structures. In this work, SiCN piezoresistive thin films are prepared by magnetron sputtering, and the influence of sputtering power on their piezoresistive properties and interfacial strengths are studied. The gauge factors of SiCN films range from 2786 to 4714 at various sputtering powers, which are significantly higher than the range from 46 to 1105 for existing piezoresistive thin films. Upon an optimal sputtering power of 75 W for silicon nitride target, the obtained SiCN sample show the largest gauge factors in a large range from 0.5 to 3.4 MPa. Furthermore, the SiCN thin films present high critical loads up to 36.5 N in scratch tests and indicate strong interfacial adhesion with substrate. This work provides an important reference for developing SiCN-based MEMS pressure sensors.

In this study, Si@Cu composite anode material is prepared by magnetron sputtering method and applied for lithium-ion batteries. The Cu component with higher intrinsic conductivity can help to improve the conductivity of the Si particles effectively. The irregularly shaped micro-sized Si particles have reduced agglomeration effect compared with nano-sized particles. In order to further relieve the volume effect of the Si particles during charging and discharging processes, carbon layer is further introduced, which will further boost the conductivity and the cyclic performance. The Si@Cu@C composite electrode exhibits a remarkably improved electrochemical performance with reversible capacity of 1130 mAhg−1 after 100 cycles with coulombic efficiency of 99.3%. The methods used for the preparation of the Si@Cu and Si@Cu@C composite materials are both mass-productive, which is benefit for their practical applications. Moreover, magnetron sputtering method used for composite power preparation has broad application prospects in micro-sized composite material preparation.

In this work, deposition time and RF power was shown to significantly influence the microstructure and properties of silicon carbide (SiC) thin films deposited on aluminum substrates by radio-frequency (RF) magnetron sputtering. Three different deposition times of 40, 60 and 75 min and at RF powers of 90 and 120 W were considered. The surface morphology of the thin films was investigated using an optical profilometer and a scanning electron microscope (SEM). The Vickers hardness test was also used to determine the hardness of the films. Grain size measurements revealed that increasing the deposition time and RF power results in larger SiC grains. Moreover, the surface roughness also increased with deposition time, however a decrease in roughness was observed when the RF power was increased from 90 to 120 W. The hardness of the SiC thin films generally increased with both deposition time and RF power, with the power having a more pronounced effect on the film hardness.

Owing to the potential ability of metal nanoparticles to enhance the performance of energy storage devices, their catalytic performance has been studied by many researchers. However, a limited number of suitable characterization techniques does not allow fully elucidating their catalytic mechanism. Herein, high-accuracy operando magnetometry is employed to investigate the catalytic properties of a cobalt oxide electrode for lithium-ion batteries fabricated by magnetron sputtering. Using this technique, the magnetic responses generated by the Co-catalyzed reversible formation and decomposition of a polymer/gel-like film are successfully detected. A series of CoO/Co films are prepared by magnetron sputtering in different environments at various sputtering times to study the influence of Co content and film thickness on their catalytic properties. It is clearly demonstrated that increasing the Co content enhances the magnetic signal associated with the catalysis process. Furthermore, decreasing the electrode thickness increases the area affected by the catalytic reactions, which in turn enhances the corresponding magnetic responses. The obtained results experimentally confirm the catalytic activity of Co metal nanoparticles and provide a scientific guidance for designing advanced energy storage devices. This work also shows that operando magnetometry is a versatile technique for studying the catalytic effects of transition metals.

Ag has been incorporated into the CZTS film through post-doping by magnetron sputtering to decrease the CuZn anti-site defect. Efforts have been dedicated to optimize the Ag sputtering time and 60 s will be the best as surveyed from the SEM, XRD and Raman spectra. Then the broad-band self-driven heterostructure photodetector has been manufactured by combining the CZTS and inverted pyramid n-Si (IP n-Si). The device represents the first-rank property under the irradiation of 5 mW, 780 nm LED with 0 V bias with the responsivity and detectivity of 7.2 mA/W and 4.98 × 1010 Jones respectively. The device can persist excellent linearity when enduring a 40 mW-80 mW, 980 nm NIR laser with 0 V bias. The comprehensive performance becomes the best under the irradiation of a 50 mW laser. The responsivity and detectivity are 1.22 mA/W and 1.98 × 1010 Jones. The device can also work stably as the laser changes from 1 Hz to 15 kHz. The rise time and decay time are 93.3 μs and 141.0 μs respectively. These results open up an innovative application for CZTS to build a broad-band self-driven photodetector as a window-layer.

Due to the scarcity of indium (In) in the earth and its potential harm to individuals, the development of In-free transparent conductive film is considered crucial. In this work, In-free SnO2:Sb/Au/SnO2:Sb (ATO/Au/ATO, SAS) tri-layer films with high transparency and conductivity were successfully prepared on polycarbonate (PC) substrates by RF and DC magnetron sputtering at room temperature. The influence of the Au layer thickness on microstructure, electrical and optical performances was systematically studied after fixing the ATO thickness to 50 nm. It was indicated by X-ray diffraction patterns that ATO is amorphous and Au is oriented along (111). The trend of increasing and then decreasing light transmission with Au layer thickness was observed in both experimental and simulation results. The improved figure of merit (FoM, 1.89 × 10−2 Ω−1) was achieved in SAS tri-layer film, the resistivity and average transmittance of which was lowered to 7.50 × 10−5 Ω cm and 81.4%, respectively, when Au layer thickness is 11 nm. Moreover, the mechanism of the variation of optical and electrical properties at different Au layer thickness was proposed. Particularly, the SAS tri-layer films also exhibit superior flexibility, durability and adhesion. These results demonstrate SAS tri-layer films are promising alternative to ITO in flexible electronics applications.

Amorphous tungsten (VI) trioxide thin films were deposited on rigid Ni-foam and flexible PET substrates using RF magnetron sputtering technique. The impacts of sputtering RF power on microstructure, morphology, compositional and electrochemical properties of the deposited thin films were investigated by using Raman, FE-SEM, XPS and electrochemical techniques. The thicknesses of the deposited films were increased from 70 to 105 μm as a function of RF power. The films contain uniform nanoparticles and the observed sizes are in the range of 25–70 nm. The films of WO3@Ni and WO3@PET deposited at an optimum RF power of 100 W exhibited the high areal capacitance of 22.01 mF/cm2 and 9.76 mF/cm2 with good cyclic retention of 81.03% and 69.53% after 5000 cycles respectively. Further, two solid-state symmetric supercapacitor (SSC) devices were assembled which shows pseudocapacitive behaviour. The devices delivered moderate energy densities of 0.48 μWh/cm2 and 0.20 μWh/cm2 and power densities of 312 μW/cm2 and 150 μW/cm2 for rigid Ni foam and flexible PET based devices respectively. This result demonstrated that the binder free in-situ deposition of WO3 films deposited at an optimum RF power of 100 W is more suitable to fabricate supercapacitor devices.

Using wide-band (0.5-6.5 eV) spectroscopic ellipsometry we study ultrathin [Bi(0.6-2.5 nm)-FeNi(0.8,1.2 nm)]N multilayer films grown by rf sputtering deposition, where the FeNi layer has a nanoisland structure and its morphology and magnetic properties change with decreasing the nominal layer thickness. From the multilayer model simulations of the ellipsometric angles, Psi(omega) and Delta(omega), the complex (pseudo)dielectric function spectra of the Bi layer were extracted. The obtained results demonstrate that the Bi layer can possess the surface metallic conductivity, which is strongly affected by the morphology and magnetic properties of the nanoisland FeNi layer in the GMR-type Bi-FeNi multilayer structures., 6 pages, 4 figures

Herein, the tungsten trioxide (WO3) nanostructure thin films with different morphologies are firstly fabricated by magnetron sputtering with glancing angle deposition technique (MS-GLAD), followed by the post annealed treatment process in air ambient for 2 h. It is demonstrated that the geometry of MS-GLAD setup, mainly substrate position, played a crucial role in determining the morphology, crystallinity, optical transmittance, and photo-electrochemical (PEC) performance of the WO3 nanostructured thin film. With the different substrate positions in the MS-GLAD system, the WO3 nanorod film layer could be precisely changed to combine an underlying dense layer with a nanorod layer and then nanocolumnar film. Moreover, the prepared samples' chemical composition and work function are studied by X-ray photoelectron spectroscopy (XPS) and ultraviolet photoelectron spectroscopy (UPS), respectively. The combining WO3 nanostructure produced high PEC efficiency compared to the single layer of the WO3 nanorods sample and the dense WO3 thin film sample. Thus, morphology-controlled nanostructure film based on the MS-GLAD technique in our study provides a simple approach to enhance the photo-anode for PEC water splitting application.

Silver films with a thickness below 50 nanometer were deposited on glass using DC magnetron sputtering. The chemical stability of the films was investigated by exposure of the film to a droplet of a HCl solution in a humid atmosphere. The affected area was monitored with a digital microscope. The affected area increases approximately linearly with time which points to a diffusive mechanism. The slope of the area versus time plot, or the diffusivity, was measured as a function of the acid concentration, the presence of an aluminum seed layer, and film thickness. The diffusivity scales linearly with the acid concentration. It is shown that the diffusivity for Al-seeded Ag films is much lower. The behavior as function of the film thickness is more complex as it shows a maximum.

International audience; Quaternary germanium-antimony-selenium-tellurium (Ge-Sb-Se-Te) thin films deposited from Ge19.4Sb16.7Se63.9-xTex (x = 5, 10, 15, and 20) glass-ceramics targets by radio frequency magnetron sputtering were studied using laser ablation quadrupole ion trap time of flight mass spectrometry. Binary, ternary, and quaternary GeaSbbSecTed clusters were formed and their stoichiometry was determined. By comparison of the clusters obtained from quaternary Ge-Sb-Se-Te thin films and those from ternary Ge-Sb-Te materials, we found that Ge-Te species are not detected from the quaternary system. Furthermore, Ge-Se and Se-Te species are missing in mass spectra generated from Ge-Sb-Se-Te thin films. From the Ge-Sb-Se-Te thin films, 16 clusters were detected while ternary Ge-Sb-Se glasses yielded 26 species. This might be considered as a signal of higher stability of Ge-Sb-Se-Te thin films which is increasing with a higher content of Te. The missing (Se-2(+), GeaSb+ (a = 1-4), and GeSec+ (c = 1, 2)) and new (Ge+ and SbbTe+ (b = 1-3)) clusters may indicate that some of the structural features of the films (Ge2Se6/2 and Se2Sb-SbSe2) were replaced by (GeSe4-x,Te-x and SbSe3-xTex) ones. In addition, when comparing the stoichiometry of clusters formed from Ge-Sb-Se-Te thin films with those from the mixtures of the elements, only Sb-3(+) and SbSe+ were observed in both cases. The knowledge gained concerning clusters stoichiometry contributes to the elucidation of the processes proceeding during plasma formation used for the chalcogenide thin films deposition.

In this work, ZnO films are deposited by magnetron sputtering [using direct current (DC)], on polished silicon substrate Si(100) (non-etched), etched for 1 min, 5 min, 10 min and 15 min. The effect of etched silicon substrate on structural, morphological, and optical properties of ZnO films has been investigated. A new nanostructure can be obtained by mean of modification in morphology of substrate. The etching of the substrate was effectuated by means of dry plasma at different time and they compared with non-etched substrates. AFM and SEM images have been used to investigate the morphology behaviors of ZnO films growth on etched and non-etched silicon substrates. Optical properties were studied in details, photoluminescence (PL) showed that the intensity of ZnO films have been increased by increasing the substrate etching time from 0 to 15 min, which were associated with the crystallographic properties [for (002) orientation] using X-ray diffraction (XRD). That may be related to the decrease of grain size and roughness morphology increasing with the etching time. FTIR and MicroRaman spectra of films show vibrational modes characteristic of ZnO materials and they were related with morphology and structural of the films. In addition, the variation of ethylene glycol contact angle data (ECA) related to roughness of the ZnO films deposited on etched Si substrate at different times were studied. The ZnO films on etched substrate were interesting in optoelectronic purpose as well as for gas sensor in future work of our team.

Noble-metal-free surface-enhanced Raman scattering (SERS) substrates have attracted great attention for their abundant sources, good signal uniformity, superior biocompatibility, and high chemical stability. However, the lack of controllable synthesis and fabrication of noble-metal-free substrates with high SERS activity impedes their practical applications. Herein, we propose a general strategy to fabricate a series of planar transition-metal nitride (TMN) SERS chips via an ambient temperature sputtering deposition route. For the first time, tungsten nitride (WN) and tantalum nitride (TaN) are used as SERS materials. These planar TMN chips show remarkable Raman enhancement factors (EFs) with ∼ 105 owing to efficient photoinduced charge transfer process between TMN chips and probe molecules. Further, structural engineering of these TMN chips is used to improve their SERS activity. Benefiting from the synergistic effect of charge transfer process and electric field enhancement by constructing a nanocavity structure, the Raman EF of WN nanocavity chips could be greatly improved to ∼ 1.29 × 107, which is an order of magnitude higher than that of planar chips. Moreover, we also design the WN/monolayer MoS2 heterostructure chips. With the increase of surface electron density on the upper WN and more exciton resonance transitions in the heterostructure, a ∼ 1.94 × 107 level EF and a 5 × 10−10 M level detection limit could be achieved. Our results provide important guidance for the structural design of ultrasensitive noble-metal-free SERS chips.

The diamond-like carbon- (DLC-) coating technique is used in the sliding parts of automotive engines, among other applications, to reduce friction and wear. In this work, DLC has been coated on the Aluminium 5051 sample to assess the mechanical and tribological properties. A sputtering deposition mechanism is used, and the DLC is coated using a graphite target. The developed DLC coatings are tested for adhesion strength, hardness, chemical composition using XRD, and wear behaviour. The developed DLC thin films have considerably increased the wear behaviour of the Aluminium 5051 sample and have fulfilled the objective of this study. The XRD data indicated the presence of amorphous carbon in the coating with a threefold increase to the hardness of the naked aluminium. This study provides insight into improving the aluminium wear resistance by developing a considerably hard coating.

The doping of two-dimensional materials provides them with tunable physical properties and broadens their application. In this study, the doping of tungsten disulfide with metallic Sn atoms via a co-sputtering technique was demonstrated. In particular, WS2 was deposited by radio frequency (RF) magnetron sputtering, while Sn atoms deposited by DC sputtering become substitutional dopants. It was revealed that the metallic tungsten atom, and in some cases sulfur vacancies, in the WS2 atomic layer created by RF magnetron sputtering were partially filled/substituted by metallic Sn atoms. The Sn-doped WS2 layers exhibited n-type doping behavior with remarkable opto-electronic properties (bandgap 2.09 eV, mobility 7.84 cm2/V·s and resistivity 2.81 × 103 Ω-cm for 1 min Sn doping) suitable for photovoltaic applications. Overall, this technique facilitates better control of the dopant distribution than the traditional approach.

SiCN thin film is one of the most attractive silicon-based materials due to its excellent electrical, mechanical and optical properties. In this study, SiCN thin films have been prepared by the radio frequency reactive magnetron sputtering method under different sputtering power, pressure, and substrate temperature. The microstructure, morphology, and the optical and field emission properties of SiCN thin films were performed. The results indicated that the high-quality SiCN thin films have been successfully prepared and it is proved that these properties can be tailored by the preparation conditions. A main near ultraviolet light emission line at around 370 nm in SiCN thin films makes it suitable for the development of optoelectronic devices. This study can provide novel guidance for the controlled preparation of high-quality SiCN thin films by magnetron sputtering.

While single target sputter deposition appears very attractive to prepare kesterite Cu2ZnSnS4 (CZTS) thin films for photovoltaic applications, the growth of secondary phases arising as a consequence of stoichiometric deviation stemming from variation in sputter yield of elements must be prevented. Here, we demonstrate growth of phase pure kesterite CZTS thin films by RF magnetron sputtering of a single target by intuitively manipulating the target composition and post-sulfurization process carried out in a quasi-open environment using sulfur flakes. The influencing mechanism of post-sulfurization process was elucidated from systematic variation in the dwell time, temperature and the sulfur amount. A high temperature or a shorter dwell time yielded a small-grained microstructure associated with the presence of secondary phases. Phase pure CZTS films with better microstructural features were obtained for sulfurization at 500 °C for 60 min with 1.0 g of sulfur flakes. This film exhibited an optical bandgap of ∼1.58 eV indicating its photovoltaic potential. A device in the Mo/CZTS/Ag configuration showed typical features of a Schottky junction. The obtained current–voltage characteristic was analyzed to estimate saturation current, ideality factor and series resistance in correlation with the properties of the CZTS film.

Metastable phase in tungsten film is of great interests in recent years due to its giant spin Hall effects, however, little information has been known on its nucleation, growth and phase transformation. In this paper, a 900 nm-thick tungsten film with double-layer structure (α-W underlayer and β-W above it) was produced on SiO2/Si substrate by high vacuum magnetron sputtering at room temperature. The structural properties of β-W were systemically investigated by X-ray diffraction, transmission electron microscopy, thermodynamic calculation, first-principle and phase-field simulations. It is found that the β-W nucleation is energetically favoured on the SiO2 surface compared to the α-W one. As the film thickening proceeds, β-W[211] turns to be preferred direction of growth owing to the elastic strain energy minimization, which is verified by phase-field simulations. Moreover, the β → α phase transformation takes place near the film-substrate interface while the rest of the film keeps the β-W phase, leading to a double-layer structure. This localized phase transition is induced by lower Gibbs free energy of α-W phase at larger grain sizes, which can be confirmed by thermodynamic calculation. Further in-situ heating TEM analysis of the as-deposited film reveals that the β→α phase transformation is fulfilled by α/β interface propagation rather than local atomic rearrangements. Our findings offer valuable insights into the intrinsic properties of metastable phase in tungsten.

Silicon nitride (SiNx) thin films, owing to their high hardness and great insulation performance, show a great prospect for application in smart temperature-measurement tools. However, their properties depend on the deposition conditions, and the high temperatures during cutting process affects the insulation function of these films. In the current work, SiNx thin films were prepared on YG8 cemented carbide by middle-frequency magnetron sputtering technology. Stylus profiler, atomic force microscope (AFM), X-ray photoelectron spectroscopy (XPS), Scanning Electron Microscope (SEM), and electrochemical analysis tester were applied to investigate the influence of various sputtering currents on microstructure, chemical composition, and electrical properties of SiNx thin films. The results revealed the amorphous structure of SiNx thin films. The sputtering current showed the impetus effect on the deposition rate and roughness of the films. As the sputtering current increased, the isolated islands, initially formed on the carbide substrates, transformed into the uniform and dense film structure. High sputtering current was conducive to the dissociation of N2 and to the formation of the SiNx phase in the films. Finally, annealing at 500 °C caused the failure of Si-N bonds in the film, which deteriorated the insulation performance of the latter at high temperatures at high temperatures.

CrMoSiCN/Ag coatings were deposited on Ti6Al4V alloys at the trimethylsilane flow of 15 sccm using closed-field unbalanced magnetron sputtering, and their microstructures were observed and analyzed using SEM, XRD, XPS and TEM, respectively. The coatings’ mechanical properties were measured using nano-indenter. The tribocorrosion characteristics of Ti6Al4V and CrMoSiCN/Ag coatings were investigated in seawater using tribocorrosion tester. The results revealed that the nanocomposite coatings consisted of (Cr, Mo)N solid solution, Ag nanocrystal and amorphous SiCNx matrix. As the Ag target current increased to 1.0 A, a large amount of Ag nanoparticles were observed on the coating surface. The coating hardness initially increased to 21.0 ± 0.7 GPa at the Ag target current of 0.4 A and then declined. After the Ag element was added into coatings, their tribocorrosion characteristics were improved. The tribocorrosion characteristics of coatings were much better than those of Ti6Al4V. The tribocorrosion characteristics of CrMoSiCN/Ag coating at the Ag target current of 1.0 A were the best in seawater.

In this article, we studied the annealing process of AuCu layers deposited on TiO2 nanotubes (NTs) conducted in various atmospheres such as air, vacuum, argon, and hydrogen in order to obtain materials active in both visible and UV-vis ranges. The material fabrication route covers the electrochemical anodization of a Ti plate, followed by thin AuCu film magnetron sputtering and further thermal treatment. Scanning electron microscopy images confirmed the presence of spherical nanoparticles (NPs) formed on the external and internal walls of NTs. The optical and structural properties were characterized using UV-vis, X-ray diffraction, and X-ray photoelectron spectroscopies. It was proved that thermal processing under the argon atmosphere leads to the formation of a CuAuTi alloy in contrast to materials fabricated in air, vacuum, and hydrogen. The electrochemical measurements were carried out in NaOH using cyclic voltammetry, linear voltammetry, and chronoamperometry. The highest photoactivity was achieved for materials thermally treated in the argon atmosphere. In addition, the Mott-Schottky analysis was performed for bare TiO2 NTs and TiO2 NTs modified with gold copper NPs indicating a shift in the flatband potential. Overall, thermal processing resulted in changes in optical and structural properties as well as electrochemical and photoelectrochemical activities.

This work aims to study Cu films, and Cu-Co bilayer deposited using DC Magnetron sputtering system on silicon substrates. It can be seen that as the thicknesses of films were increased, the grain s...

TiN films with different thicknesses (17.9–102.8 nm) were prepared using rf magnetron sputtering to study the effect thickness on the plasmonic, electrical, and optical properties. X-ray diffraction revealed the amorphous-like structure for thinner films with thicknesses lower than 50.3 nm, whereas polycrystalline of face-centered cubic TiN structure was observed for thicker films. Scanning electron microscopy observations revealed rounded nano-crystallites morphology for TiN films. The EDAX depicted oxygen in the TiN films which attributed to the residual oxygen inside the sputtering chamber and to the partial surface oxidation resulted from the exposure to atmospheric air. As the thickness increased from 17.9 to 102.8 nm, the carrier concentration increases from 1.47 × 1022 to 3.51 × 1022 cm−3 and the carrier mobility increased from 0.091 to 0.489 cm2/V.s, which resulted in a resistivity decrease from 4.65 × 10–3 to 3.64 × 10–4 Ω cm. Two absorption bands around 250 and 1000 nm were observed. The band around 1000 nm was ascribed to the localized surface plasmon resonance (LSPR) and increased with increasing the film thickness. The optical band gap and refractive index values decreased monotonically with increasing the film thickness. It is also inferred that the thickness has a strong influence on the values of real and imaginary parts of the dielectric function. Applying various figures of merit indicated that the prepared TiN films are probably not practical for LSPR device fabrication however they are probably suitable for practical transformation optics and superlens device applications.

In the present research, the TiN/Ti multilayer coatings with different layers were fabricated on Ti6Al4V substrates with same deposition time by high-power DC reactive magnetron sputtering. Their microstructure, phase constituent, mechanical properties and wear behavior were studied to explore the influence of the layer number. The results reveal that increasing of layer number in TiN/Ti multilayer coatings refines the grains and promotes the transformation of the crystal orientation preference of the TiN layer from (111)TiN to a mixture of (111)TiN, (200)TiN and (220)TiN. Moreover, the thickness of the TiN/Ti multilayer coating increases with the increased layer number. The Ti interlayer and TiN layer have a sinuous interface at the atomic scale with many dislocations, and no orientation relationship between these layers is found. With the increasing of layer number, the elastic modulus and hardness of the TiN/Ti multilayer coatings increase firstly and then decrease. The two-layer and four-layer TiN/Ti multilayer coatings obtain the maximum elastic modulus and hardness, respectively. Moreover, the increased layer number improves the adhesion of the TiN/Ti multilayer coating obviously, and the twelve-layer TiN/Ti multilayer coating obtains the highest adhesion, which could be ascribed to the relaxation of interfacial stress. The increased Ti interlayers promote the diversification of the friction coefficient of the TiN/Ti multilayer coatings. With the proceeding of wear test, the friction coefficients of the one-layer and two-layer TiN/Ti multilayer coatings maintain an increasing tendency, but the friction coefficients of the four-layer, eight-layer and twelve-layer TiN/Ti multilayer coatings drop at final, middle and initial stage, respectively. The one-layer, two-layer and four-layer TiN/Ti multilayer coatings have similar wear rates which are less than one twentieth of the wear rate of the Ti6Al4V substrate. While the wear rates of the eight-layer and twelve-layer TiN/Ti multilayer coatings are higher than that of the Ti6Al4V substrate.

The magnetron sputtering has been used to prepare metal foam wicks for heat pipes by coating the surface of copper foam with zinc oxide (ZnO) nanoparticles. The main properties, including microscop...

In this study, we successfully synthesized a Pd/ZnO/Ni hierarchical porous array-film catalyst by electrodeposition and magnetron sputtering with the assistance of the monodisperse colloidal sphere template. Structural characterisation indicated that a layer of Pd nanoparticles was uniformly grown on the ZnO/Ni ordered bowl-like micro/nano array film. Electrochemical measurements in alkaline solution demonstrated that the as-grown array film had outstanding electrocatalytic activity for methanol oxidation. The specific activity of the Pd/ZnO/Ni porous array film was up to 130.1 mA cm−2. The corresponding mass activity (812.7 mA mg−1) was 6 times higher than that of commercial Pd/C catalyst (134.8 mA mg−1), and the stability was also much better than the commercial one. These excellent electrochemical properties can be attributed to the unique hierarchical porous structure, which offers a high specific surface area for the methanol reaction, and ZnO intermediate layer, which effectively removes the poisoning species from the Pd sites through the strong oxidative hydroxyl radicals.

ZnO nanorod arrays (NRs) with a large number of sharp tips and uniform shapes were grown on the carbon cloth (CC) by a simple hydrothermal method. Titanium nitride (TiN) nanoparticles with various thicknesses were deposited on the ZnO NRs by magnetron sputtering to obtain ZnO/TiN core-shell arrays. Field emission (FE) performance of ZnO NRs show close dependence on TiN coating thickness. The turn-on field first decreases and then increases with increasing TiN coating thickness from 60 nm to 300 nm. The arrays with a design architecture can strike a balance between increased emission sites and limited field shielding effects. ZnO/TiN240 core-shell NRs have the lower turn-on electric field at 0.79 V/μm and the higher current densities at 9.39 mA/cm2. The field enhancement factor (β) of ZnO/TiN240 is about 3.2 times that of the bare ZnO NRs. On the other hand, the electrochemical properties were improved due to the formation of core-shell heterojunction on the ZnO/TiN interface and porous structure, which makes the ion and charge transport more convenient. Hence, this work not only revealed that the ZnO/TiN core-shell structure exhibited excellent improvement in both FE and supercapacitors applications, but also that growing arrays on CC was expected to achieve flexible display.

Silica nanospheres have been explored much for drug delivery, photocatalysis, sensors and energy storage applications. It also acts as a template for Surface-Enhanced Raman Spectroscopy (SERS) substrates. Uniform nanostructures at low cost with high reproducibility are the major challenges in SERS substrate fabrication. In the present work, silica nanospheres were synthesized using stober method and deposited on to glass slides using Vertical deposition techniques. Different size/thickness of Silver (Ag) nanoparticles were deposited onto silica thin films using sputter deposition technique. The monodispersity of silica nanospheres and size of silver nanoparticles (10 nm, 20 nm and 30 nm) were confirmed by FESEM analysis. The structural properties were confirmed through XRD. UV–Vis analysis revealed that the plasmonic properties of Ag@SiO2 give high surface plasmons for 30 nm thickness of silver. The binding energy of Ag@SiO2 confirmed through XPS spectrum. The fabricated SERS substrates were used to detect Rhodamine 6G (R6G), Methylene blue (MB), Methylene violet (MV) and Methyl orange dyes as an analyte molecule with a limit of detection at about 10−11 mol/L. The addition of SiO2 nanospheres decreases the Ag oxidation rate and increases their stability. The maximum enhancement factor (1.5 × 107) achieved for 30nm thickness of Ag@SiO2. The results and technique establish the potential applications and reproducible SERS substrate.

Transition metal dichalcogenides (TMDs) are easily oxidized in the humid atmosphere, leading to a decrease in their lubricating properties and limiting their application. In this study, a MoS2/WS2 multilayer film doped with tantalum (MoS2/WS2-Ta) is fabricated by magnetron sputtering to improve the corrosion and oxidation resistance of TMDs. Results show that doping of Ta makes the structure of the MoS2/WS2 multilayer film more compact, and the MoS2 and WS2 crystals exhibit a stronger (0002) preferred orientation than that of un-doped sample. Such compact structure and (0002) preferred orientation of MoS2/WS2-Ta can realize a high corrosion resistance, i.e., a more positive corrosion potential and a lower corrosion current density in comparison with the MoS2/WS2 multilayer. Furthermore, the friction properties of MoS2/WS2 multilayer film doped with 1.1 at% of Ta are improved remarkably under both of high temperature (370 °C in air) and vacuum conditions, the result is attributed to its high mechanical properties and (0002) preferred orientation. In a word, the combination of multilayer structure and doping of Ta into the films is a promising approach to accurately design the TMDs toward a wide temperature range and environmentally adaptive lubricants.

Ultrawide bandgap Al0.7Ga0.3N MESFETs with refractory Tungsten Schottky and Ohmic contacts are studied in 300–675 K environments. Variable-temperature dc electrical transport reveals large ON-state drain current densities for an AlGaN device: 209 mA/mm at 300 K and 156 mA/mm at 675 K in the ON-state (25% reduction). Drain and gate currents are only weakly temperature-dependent, suggesting potential for engineering temperature invariant operation. The ON-/ OFF-ratio is limited by OFF-state leakage through the gate, which is attributed to damage from sputter deposition. Future work using refractory metals with larger work functions that are deposited by electron beam deposition is proposed.

We investigated the defect states and optoelectrical properties of methylammonium lead iodide (MAPbI3) perovskite films synthesized via a two-step dry process. To synthesize MAPbI3 thin films, PbI2 thin films were deposited via rf magnetron sputtering and were subsequently exposed to methylammonium iodide (MAI) vapor to synthesize MAPbI3 thin films. By using deep level transient spectroscopy and space-charge-limited current methods, the defect density of the perovskite films was proven to be reduced by about 6 times as the reaction temperature increased from 90 to 110 °C . At a high reaction temperature of 130 °C , the deformation process could occur, resulting in a rising trap density within the perovskite film. Along with a significant decline in defect density, the photoresponsivity of films fabricated at 110 °C were higher by about 2.05 and 18.76 times more than those of samples prepared at 100 and 130 °C , respectively. An excellent detectivity of 1.17 × 1013 Jones was observed from the sample synthesized at 110 °C , demonstrating the superiority of a two-step dry process.

C doped CrTiN films were deposited on 316L stainless steel by magnetron sputtering technology to investigate corrosion resistance and electrical conductivity. The sputtering current of the C target alter to obtain various C contents. The carbon target currents are 0 A, 3 A and 6 A, respectively. The result of SEM confirms that deposited films have a dense and uniform microstructure. CrTiN coating consist of Cr, CrN and TiN phases. With the increase of C carbon target currents, Cr crystal structure vanishes, and the amorphous carbon and carbides appear. The result of the potentiodynamic polarization test in the simulate PEMFC environment reveals that C doped CrTiN coating can improve samples’ corrosion resistance. At 1.1 V (vs. SHE) potentiostatic tests, the C-6A has the lowest current density, 6.09 × 10−7 A/cm2. Interfacial contact resistance decreases with the addition of C atoms. The C-6A coated sample has the lowest interfacial contact resistance values, 5.5 mΩ cm2.

—The influence of the parameters of dc reaction magnetron sputtering of two monoelement targets (Ti, Pb) onto substrates made of a VT6 titanium alloy and 12Kh18N10T steel on the microhardness, the phase composition, and the texture of the sputtered composite coatings is studied. The coatings consist only of Pb and PbO at a lead cathode current of 0.2 A and also include TiN at a current of 0.1 A. The coatings on the VT6 alloy have a higher microhardness as compared to the coatings on 12Kh18N10T steel, which is due to the nitriding-assisted hardening of titanium substrate. The following correlation of the texture with the microhardness is found: the (111) pole density increases threefold and the microhardness of coatings decreases sharply when the ratio of the argon and nitrogen flow rates increases from 2.08 to 4.3.

Using the reactive DC magnetron sputtering of two separate single-element Ti and Pb targets, a TiN–Pb composite coating was deposited onto a substrate made of VT6 titanium alloy. The studies are carried out on currents on the Pb cathode of 0.2 and 0.1 A and two fixed values of the argon flow rate of 6.0 or 8.5 cm3/min, as well as the flow rate of nitrogen supplied to the chamber varying from experiment to experiment. The composition of the coatings is determined by energy dispersive analysis. It is shown that the amount of lead in the coatings ranges from 0.5 to 16%, depending on the current on the Pb cathode and reactive gas consumption N. The microhardness and wear of the coatings are determined for each deposition mode. Depending on the ratio of argon and nitrogen fluxes, the thickness of the coatings varies from 1.9 to 5.2 μm. The effect of the deposition parameters of magnetron TiN–Pb coatings on the structure and phase composition is investigated by the X-ray diffraction method. It is shown that, at a current value of 0.2 on the Pb cathode, the coating consists of Pb and PbO and, at a current of 0.1 A, it consists of TiN, Pb, and PbO, while an increase in the ratio of argon and nitrogen fluxes leads to an increase in the fraction of TiN, the intensity of surface saturation, titanium substrate with nitrogen, microhardness, and wear resistance. Under all deposition conditions, the TiN coating is characterized by a typical texture (111), the intensity of which varies nonmonotonically.

To date, the deposition of AlGaN thin film using the co-sputtering technique at room temperature has not been reported yet. The use of AlGaN for electronic devices has been widely known because of its ultra-wide bandgap. However, to deposit the AlGaN thin film and achieved high quality of AlGaN films, higher temperature or extra time deposition are needed, which is not compatible with industrial fabrication process. Here, a co-sputtering technique between two power supplies of magnetron sputtering (which are RF and HiPIMS) is introduced to deposit the AlGaN thin films. The AlGaN thin films were deposited at various RF power to study their effect on structural properties and morphology of the thin films. AlGaN films were sputtered simultaneously on silicon (111) substrate for short time and at room temperature using GaN and Al target. Then, the films were characterized by X-ray diffraction (XRD), atomic force microscopy (AFM), and surface profiler to study their properties. XRD shows the GaN (101) and (013) plane for the AlGaN deposited at RF power of 30 W. Also there only GaN (101) for the AlGaN with 50 W RF power. Yet, the 70 W RF power shows the amorphous structure of AlGaN. The roughness and the grain size of AlGaN film from AFM analysis showed the trend of decreasing and increasing respectively. The roughness of the AlGaN films with 30 W power was 0.82 nm, 0.85 nm for 50 W, and 0.46 nm for 70 W RF power. The grain size of the AlGaN films was 30.06 nm, 32.10 nm, and 37.65 nm for RF power of 30 W, 50 W, and 70 W respectively. The profilometer found that the thickness of the AlGaN films was decreasing with increasing of RF power. This paper can demonstrate a successful co-sputtering technique of AlGaN. Despite AlGaN crystal structure was not able to found out in the XRD analysis, the effect of RF power has been studied to give significant effects on AlGaN thin film deposition.

Simple Wheatstone bridge-giant magnetoresistance (GMR) sensors with one and two spin-valve (SV) thin films were developed for detecting magnetic nanoparticles (MNPs). SV thin films with a Ta(2 nm)/Ir20Mn80(10 nm)/Co90Fe10(3 nm)/Cu(2.2 nm)/(Co90Fe10)92B8(10 nm)/Ta(5 nm) structure were fabricated using RF magnetron sputtering on Si/SiO2 substrates. Inverse spinel-structured Fe3O4 and Fe3O4/polyethylene glycol (PEG) MNPs were synthesized by coprecipitation methods. To investigate the GMR sensor response, MNPs-ethanol (10 μL) solutions were dropped on the surface of the thin films. The following changes in Fe3O4 were observed after coating with PEG: the size of the nanoparticles increased from 11 to 13 nm, and the saturation magnetization of Fe3O4 decreased from 77.0 to 49.6 emu/g, which can be attributed to the surface modifications by PEG polymer; furthermore, the coercivity increased from 51.2 to 61.5 Oe owing to the existence of the antiferromagnetic phase α-Fe2O3. The output voltage of the GMR sensor with one and two SV thin film elements for Fe3O4 changed by 2.2 and 5.5 mV, respectively, and the output voltage decreased to 1.4 and 1.5 mV, respectively, in the case of Fe3O4/PEG. The decrease in the output voltage was caused by the decrease in the saturation magnetization of Fe3O4 after coating with PEG.

PurposeThis study aims to investigate the effect of temperature applied at the initial deposition of Aluminium Nitride (AlN) thin-film on a silicon substrate by high-power impulse magnetron sputtering (HiPIMS) technique. Design/methodology/approachHiPIMS system was used to deposit AlN thin film at a low output power of 200 W. The ramping temperature was introduced to substrate from room temperature to maximum 100°Cat the initial deposition of thin-film, and the result was compared to thin-film sputtered with no additional heat. For the heat assistance AlN deposition, the substrate was let to cool down to room temperature for the remaining deposition time. The thin-films were characterized by X-ray diffraction (XRD) and atomic force microscope (AFM) while the MIS Schottky diode characteristic investigated through current-voltage response by a two-point probe method. FindingsThe XRD pattern shows significant improvement of the strong peak of the c-axis (002) preferred orientation of the AlN thin-film. The peak was observed narrowed with temperature assisted where FWHM calculated at 0.35° compared to FWHM of AlN thin film deposited at room temperature at around 0.59°. The degree of crystallinity of bulk thin film was improved by 28% with temperature assisted. The AFM images show significant improvement as low surface roughness achieved at around 0.7 nm for temperature assisted sample compares to 3 nm with no heat applied. Originality/valueThe small amount of heat introduced to the substrate has significantly improved the growth of the c-axis AlN thin film, and this method is favorable in the deposition of the high-quality thin film at the low-temperature process.

Spectral beam splitting (SBS) films are crucial for the development of hybrid systems based on photovoltaic (PV) and concentrating solar thermal (CST) technologies. In this study, a novel double-layer SiN x /Cu SBS film was prepared via magnetron sputtering. This film was developed based on the linear Fresnel solar thermal technology used in PV/CST hybrid systems. The as-deposited film exhibited superior SBS properties, with a high transmittance of 72.9% and a reflectance of 89.7%. To optimize the optical properties, the thicknesses of the metal and SiN x layers were precisely controlled. The optimal thicknesses of the Cu and SiN x layers were determined to be 17 and 67 nm, respectively. Furthermore, the thermal stability of the SBS film was evaluated. When annealed at 50 °C, the surface of the SBS film became more uniform and smooth, and with increasing annealing time, the film became denser. No strong diffraction peaks of Cu were observed in the X-ray diffraction patterns because of the low content and poor crystallization of Cu. Atomic force microscopy investigations revealed the formation of a textured surface and a decrease in the root-mean-square roughness with an increase in the annealing time from 0 to 360 h. As a key component with considerable application potential in PV/CST hybrid systems, SBS films are currently an important research topic.

A study of image analysis of Ti1-x Alx N films deposited on corning glass substrates by a direct current (DC)/radio frequency (RF) magnetron sputtering system was performed. Atomic force microscopy (AFM) data were studied to understand how the impact of the concentration of Al content influences the 3D surface morphology as well as the surface texture parameters. The results showed that the superficial morphology was modified by the increase of Al content in the Ti1-x Alx N films, as well as the surface microtexture. It has also been observed that the Ti1-x Alx N film surface with the highest aluminum (Al) doping concentration presented a similar surface morphology to pristine titanium nitride (TiN) thin films. The Abbott-Firestone curves for all films exhibited an S-like shape suggesting topographic uniformity and Gaussian distribution of heights. An increase in surface uniformity is observed with Al concentration. The characterization of the surface morphology of Ti1-x Alx N films by the evaluation of surface statistical parameters suggests that the surface topography can be adjusted by suitable doping of aluminum and offers a deeper understanding of the applicability of these films.