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A successful hexagonal Cu 2 S p-type semiconductor thin film using DC magnetron sputtering is reported. Films with thickness gradients were deposited by taking advantage of deposition geometry and target dimensions. X-ray diffraction (XRD) analysis confirmed the exclusive formation of the hexagonal Cu 2 S phase. Elemental composition and thickness dependence with the sample position were determined using energy-dispersive x-ray spectroscopy. Optical properties, including the optical bandgap, refractive index, and extinction coefficient, were assessed by modeling transmittance spectra. The Tauc–Lorentz oscillator and Drude models were employed for this purpose. XRD data analysis successfully determined the film thickness (t X R D ) as a function of the sample position, aligning well with thickness values (t T) derived from transmittance spectra analyses. These results were further supported by film thickness values (t S E M ) obtained from cross-sectional SEM images. Charge carrier density and mobility, extracted from the optical models, were found to be consistent with DC electrical measurements. AC impedance curves were effectively modeled with RL–RC parallel circuits. The results indicate that the inductance (L) and capacitance (C) components of the films increase with decreasing film thickness. [ABSTRACT FROM AUTHOR]

Nb 3 Sn and V 3 Si thin films are promising candidates for the next generation of superconducting radio-frequency (SRF) cavities. However, sputtered films often suffer from stoichiometry and strain issues. This exploratory study investigates the structural and chemical effects of thermal annealing, both i n − s i t u and post-sputtering, on DC-sputtered Nb 3 Sn and V 3 Si films with varying thicknesses, deposited on Nb or Cu substrates. Building upon our initial studies [Howard et al., Proceedings of the SRF'21, East Lansing, MI (JACoW, 2021), p. 82.], we provide fundamental insights into recrystallization, phase changes, and the issues of stoichiometry and strain. Through annealing at 950 ° C, we have successfully enabled the recrystallization of 100 nm thin Nb 3 Sn films on Nb substrates, yielding stoichiometric and strain-free grains. For 2 μ m thick films, elevated annealing temperatures led to the removal of internal strain and a slight increase in grain size. Moreover, annealing enabled a phase transformation from an unstable to a stable structure in V 3 Si films, while we observed significant Sn loss in 2 μ m thick Nb 3 Sn films after high-temperature annealing. Similarly, annealing films atop Cu substrates resulted in notable Sn and Si loss due to the generation of Cu–Sn and Cu–Si phases, followed by evaporation. These results encourage us to refine our process to obtain high-quality sputtered films for SRF use. [ABSTRACT FROM AUTHOR]

PVD technologies, including vacuum arc evaporation and DC-magnetron sputtering, have been utilized in industrial settings since the early 1980s for depositing protective coatings. These coatings encompass a range of materials such as metal nitrides, carbonitrides, oxides, oxynitrides, and DLC, serving diverse applications such as cutting and forming tools, automotive components, and decoration. Vacuum arc evaporation generates a highly energized and ionized particle flux toward the substrate, while "classical" gas-ion-dominated direct current magnetron sputtering (DCMS) has limitations in generating ionized and energetic species of the sputtered target material. The development of High-Power Impulse Magnetron Sputtering (HiPIMS) has exhibited significant potential in addressing DCMS's limitations by enabling the production of highly energetic particles. This innovation, with its industrial applicability for protective coatings, was introduced around 2010. This paper aims to provide an industrial perspective on HiPIMS, serving as a guide for scientists and engineers in comprehending and implementing HiPIMS solutions. It covers historical context and fundamental characteristics. Basic features as well as state-of-the-art configurations of PVD systems are also described. Graphical representations of experimental results illustrate HiPIMS features, including operational modes, deposition rate effects, thickness uniformity, and sustainability, particularly in terms of energy efficiency. The discussion focuses on the application prospects, advantages, and constraints of industrially applied HiPIMS protective coatings, emphasizing cutting and forming tools, within the context of the findings presented. [ABSTRACT FROM AUTHOR]

The quest for lowering energy consumption during thin film growth by magnetron sputtering techniques becomes of particular importance in view of sustainable development goals. As large fraction of the process energy is consumed in substrate heating for the purpose of providing high adatom mobility necessary to grow dense films, the most straightforward strategy toward more environment-friendly processing is to find alternatives to thermally activated surface diffusion. One possibility is offered by high mass metal ion irradiation of the growing film surface, which has been recently shown to be very effective in densification of transition metal nitride layers grown with no external heating, such that Zone 2 microstructures of the structure-zone model are obtained in the substrate temperature Ts range otherwise typical for Zone 1 growth. The large mass difference between the incident ion and the atoms constituting the film results in effective creation of low energy recoils, which leads to film densification at low Ts. Due to their high mass, metal ions become incorporated at lattice sites beyond the near-surface region of intense recoil generation leading to further densification, while preventing the buildup of residual stress. The practical implementation of this technique discussed in this Perspective employs heavy metal targets operating in the high-power impulse magnetron sputtering (HiPIMS) mode to provide periodic metal-ion fluxes that are accelerated in the electric field of the substrate to irradiate layers deposited from direct current magnetron sputtering (DCMS) sources. A key feature of this hybrid HiPIMS/DCMS configuration is the substrate bias that is synchronized with heavy metal ion fluxes for selective control of their energy and momentum. As a consequence, the major fraction of process energy is used at sputtering sources and for film densification, rather than for heating of the entire vacuum vessel. Model material systems include TiN and metastable NaCl-structure Ti1−yAlyN films, which are well-known for challenges in stoichiometry and phase stability control, respectively, and are of high relevance for industrial applications. This Perspective provides a comprehensive overview of the novel film growth method. After presenting basic concepts, time-resolved measurements of ion fluxes at the substrate plane, essential for selective control of metal ion energy and momentum, are discussed. The role of metal ion mass, energy, momentum, and concentration is described in more detail. As some applications require substrate rotation for conformal coating, a section is devoted to the related complexity in the implementation of metal-ion-synchronized growth under industrial conditions. [ABSTRACT FROM AUTHOR]

The Cu-2 wt% Sb alloy was prepared and exposed to various heat treatments at temperatures ranging from 573 to 973 K to get distinct grain diameters. Different samples of various grain diameters were individually sputtered in an argon glow discharge for various times (0.5, 1, 2 h) using a DC magnetron sputtering device. The surface topography and microstructural features of a Cu-2 wt% Sb alloy were examined utilizing an optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD). The C u 3 S b IMC phase was found to segregate at the grain boundaries. Results showed that the topographical features of sputtered samples (grain boundaries, tiny cones, cratered cones, and etch pits) were mainly affected by grain size and sputtering time. Moreover, the mechanical properties of a Cu-2 wt% Sb alloy were examined. The parameters of the stress–strain curves (Young modulus Y, 0.2% offset stress σy0.2, fracture stress σf, parabolic work-hardening coefficient χ p , and ductility ε f \% ) were measured under different testing conditions. Generally, these stress parameters decrease as the grain diameter increases. These parameters, with the exception of ε f \% , increase as the strain rate increases, while ε f \% decreases as the strain rate increases. Additionally, selective samples of the present alloy were irradiated using γ-radiation with different doses 0.5, 1, 1.5, and 2 MGy. The Vickers microhardness of annealed and irradiated samples lowered as the grain size augmented, while it increased as the irradiation dose increased. Based on the obtained activation energy Q value of 20.65 kJ/mol., it is indicated that the predominant deformation mechanism in the Cu-2 wt% Sb alloy is the motion of dislocation through the Cu-matrix. [ABSTRACT FROM AUTHOR]

The present study uses DC magnetron sputtering for synthesis of a TiN and Ti-TiN bilayer on the surface of SS-CRM 487/1 high-speed tool steel. This coating is deposited on the substrate at 400°C. The deposited substrate is characterised by different experimental techniques. The scanning-electron microscopy (SEM) is used for film morphology, cross-sectional examination, and worn-out surfaces. The profilometer is used for measuring the film thickness and roughness. However, the nano-indentation is used to extract the intrinsic hardness and young's modulus evaluation. The ball on-disc sliding test under dry conditions is employed for tribological properties of deposited high-speed tool steels. The test results indicate the improvement in the wear resistance for the Ti-TiN bilayer except four bilayers as no of layer increases. [ABSTRACT FROM AUTHOR]

The present work demonstrates the impact of oxygen flow rates on various properties of TiO2 thin films grown using DC magnetron sputtering. The XRD studies verified the materials' polycrystalline nature. Surface roughness variation with oxygen flow rate was noticed using AFM analysis. The optical energy bandgap was found to vary between 3.42 and 3.75 eV. The electrical and photo-sensing properties of the TiO2 layer were thoroughly examined. The constructed Au/TiO2 junction exhibited a Schottky barrier with a three-order rectification ratio recorded under dark mode. The sensor parameters such as responsivity, detectivity, response time, and linear dynamic range were carefully studied. Under UV (395 nm, 0.5 mW/cm2) irradiation, the diode fabricated at 18% of oxygen flow rate (Au/TiO2-18/ITO) had a photoresponsivity of 0.209 A/W and a steady photo detectivity of 4.03 × 1010 Jones at room temperature. Remarkably, a response time of 520/133 ms was reported. Thus, our findings indicate that Au/TiO2 Schottky diodes might be beneficial for visible, transparent UV photosensors in future optoelectronic applications. [ABSTRACT FROM AUTHOR]

This research, which involved a comprehensive methodology, including depositing electroplated copper on a copper seed layer and Al-doped ZnO (AZO) thin films on textured silicon substrates using DC magnetron sputtering with varying substrate heating, has yielded significant findings. The study thoroughly investigated the effects of substrate temperature (Ts) on copper adhesion strength and morphology using the peel force test and electron microscopy. The peel force test was conducted at angles of 90°, 135°, and 180°. The average adhesion strength was about 0.2 N/mm for the samples without substrate heating. For the samples with substrate heating at 100 °C, the average peeling force of the electroplated copper film was about 1 N/mm. The average peeling force increased to 1.5 N/mm as the substrate heating temperature increased to 200 °C. The surface roughness increases as the annealing temperature of the Cu/AZO/Si sample increases. These findings not only provide a reliable and robust method for applying AZO transparent conductive films onto silicon solar cells but also underscore its potential to significantly enhance the efficiency and durability of solar cells significantly, thereby instilling confidence in the field of solar cell technology. [ABSTRACT FROM AUTHOR]

Optical losses of perovskite/silicon tandem solar cells can be effectively reduced by optimizing the thin‐film layer thicknesses. Herein, the thicknesses of DC sputtered indium tin oxide (ITO) films, which serve as the front electrode and the recombination layer connecting the subcells, are optimized to reach high transparency and good lateral charge transport simultaneously. Optical simulations of the full perovskite/silicon tandem solar cell stacks are performed to find the optimum recombination and front electrode ITO thicknesses for solar cells as well as modules. Implementation of the optimized 25 nm front electrode ITO thickness in semitransparent single‐junction perovskite solar cells increases the short‐circuit density by 1.5 mA cm−2 compared to the former reference thickness of 75 nm. Combined with an optimized 20 nm recombination ITO layer, high short‐circuit density of 20.3 mA cm−2 is reached in perovskite/silicon tandem solar cell devices, which is the highest reported value for planar front perovskite/silicon tandem solar cells to the best of knowledge. Further interface passivation enables 28.8% power conversion efficiency. [ABSTRACT FROM AUTHOR]

Early biofilm formation could be inhibited by applying a thin biocompatible copper coating to reduce periprosthetic infections. In this study, we deposited crystalline Cu-doped TiO2 films using one-step DC magnetron sputtering in an oxygen atmosphere on a biased Ti6Al4V alloy without external heating. The bias voltage varied from −25 V to −100 V, and the resultant substrate temperature was measured. The deposited coatings were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), microhardness, scratch and hydrophilicity tests, potentiodynamic polarization measurements, and antibacterial assays against S. aureus and E. coli. The findings demonstrated that when a higher negative bias is applied, the substrate temperature drops, and the anatase to rutile transformation is initiated without indicating obvious Cu-containing phases. The SEM images of the films showed spherical agglomerates with homogeneously distributed Cu with decreasing Cu content as the bias value increased. Higher bias results in the grain refinement of the thinning coatings with more lattice microstrain and more defects, together with an increase in water contact angles and hardness values. Samples biased at −75 V exhibited the highest adhesive strength between coatings and substrate, whereas the specimen biased at −50 V demonstrated higher corrosion resistance. Cu-containing TiO2 coatings with pure anatase phase composition and Cu concentrations of 2.62 wt.% demonstrated excellent bactericidal activity against both S. aureus and E. coli. The layers containing 2.34 wt.% Cu exhibited very good antibacterial properties against S. aureus, only. According to these findings, the produced copper-doped TiO2 coatings have high bactericidal qualities in vitro and may be used to prepare orthopaedic and dental implants in the future. [ABSTRACT FROM AUTHOR]

This review explores the processes involved in enhancing AlN film quality through various magnetron sputtering techniques, crucial for optimizing performance and expanding their application scope. It presents recent advancements in growing AlN thin films via magnetron sputtering, elucidating the mechanisms of AlN growth and navigating the complexities of thin-film fabrication. Emphasis is placed on different sputtering methods such as DC, RF, pulsed DC, and high-power impulse DC, highlighting how tailored sputtering conditions enhance film characteristics in each method. Additionally, the review discusses recent research findings showcasing the dynamic potential of these techniques. The practical applications of AlN thin films, including wave resonators, energy harvesting devices, and thermal management solutions, are outlined, demonstrating their relevance in addressing real-world engineering challenges. [ABSTRACT FROM AUTHOR]

The design and development of Indium Tin Oxide (ITO) thin film based piezoresistive pressure sensor is presented in this paper. ITO (90:10) nanoparticles were synthesized by green combustion method using indium and tin as precursors and, carica papaya seed extract as fuel. ITO (90:10) thin film piezoresistors were deposited using synthesized nanoparticles on AlN coated circular steel (SS 304) diaphragm using E-beam evaporation technique. Diaphragm models of different thickness (0.75, 1 and 1.25 mm) were created using ANSYS finite element analysis in order to determine the maximum stress and deflection region for applied pressure of 1 to 10 bar. ANSYS results exhibited that maximum stress and deflection occurred at the center and circumference of diaphragm. ITO thin film piezoresistors were deposited at these regions using mechanical mask. TiW metal contact was established to these ITO thin film piezoresistors using DC sputtering method. ITO thin film piezoresistive pressure sensor with TiW contact connected in Wheatstone full bridge configuration was calibrated and tested for 50 pressure cycles by applying 2 V DC supply. Sensitivity (S) of the developed ITO thin film pressure sensor was obtained as 0.686, 0.566 and 0.495 mV/bar for diaphragm thickness of 0.75, 1, and 1.25 mm pressure sensors respectively. The non-linearity (NLi) in the output response of the pressure sensors was found to be 9.14, 9.82 and 11.27% for diaphragm thickness of 0.75, 1, and 1.25 mm respectively. Hysteresis errors were found to be 0.0344, 0.0525 and 0.054 for diaphragm thickness of 0.75, 1, and 1.25 mm respectively. [ABSTRACT FROM AUTHOR]

Niobium-based oxides have garnered increased attention in recent years for their remarkable enhancement of corrosion resistance, as well as biofunctional properties of various metallic materials, including 316L SS. However, the mechanical properties of these promising coatings have not been fully elucidated. This study investigated how much the environmental conditions (air, artificial saliva, and NaCl solution) impact the wear performance of 316L SS without and with Nb2O5 coatings deposited via the reactive sputtering technique. The results exhibited a notable decrease in friction coefficient (55% in air, 18% in artificial saliva, 10% in 0.9 wt% NaCl solution), wear area (46% in air, 36% in AS, 17.5% in 0.9 wt% NaCl solution), and wear rate (44.0% in air, 19.5% in AS, 12.0% in 0.9 wt% NaCl solution). Ultimately, the results obtained in the present study elucidate the synergistic mechanisms of corrosion and wear in 316L SS containing Nb2O5 coatings, highlighting its significant potential for applications in the biomedical sector. [ABSTRACT FROM AUTHOR]

In this study, titanium metal (99.99%) was deposited on quartz glass substrate test specimens by DC magnetron sputtering. Thereafter, radio-frequency magnetron sputtering was used to create an oxide layer of ITO:Ga (97.3 at%) to form a final dual-layer transparent and conductive film on the glass substrate. The film was then annealed at different temperatures under vacuum. The thermal energy rearranged the internal crystalline structure, and this reduced the number of crystalline defects. The multilayer structure of the dual-layer film was explored after annealing: the film thickness, electrical properties, transmission properties, surface structure, grain size, and quality factors were all analyzed. The results showed that the electrical properties of ITO:Ga/Ti improved after annealing at 500 °C (100 W; 30 min) and that the resistivity was 6.51 × 10-4 O·cm. The average penetration of ITO:Ga/Ti after annealing at 400 °C was 87.52%, and after annealing at 500 °C, it was 89.70%. The figure of merit was the optimal value of 4.78 × 10-3 O-1 after annealing at 500 °C. [ABSTRACT FROM AUTHOR]

TiTaZrNb medium entropy coatings and their nitride forms (TiTaZrNb)Nx were synthesized by direct current magnetron sputtering. The study evaluated the bias voltage affects microstructure, chemical and phase composition of the metallic coatings. Also, the effect of nitrogen flow on the microstructural and tribological properties of the corresponding nitrides was studied. A change in the crystalline structure from BCC for TiTaZrNb coatings to FCC for (TiTaZrNb)Nx was observed. It was associated with the incorporation of nitrogen into the matrix and the consequent formation of a solid solution of (TiTaZrNb)Nx. An increase in the hardness and residual stresses of the metallic coating was observed with increasing bias voltage to − 130 V and of the nitride coating with increasing nitrogen flow to 12 sccm, reaching hardness values of 12.8 GPa and 25 GPa, respectively. A slight reduction in the hardness of the deposited nitride coating was observed at the higher nitrogen flow of 15 sccm, probably due to the formation of the TiN and ZrN phases. The higher hardness and lower wear rate of the (TiTaZrNb)Nx nitride coatings compared to the uncoated M2 steel samples demonstrate the protective effect against wear of these coatings. [ABSTRACT FROM AUTHOR]

The evolution of Sb2Se3 heterojunction devices away from CdS electron transport layers (ETL) to wide bandgap metal oxide alternatives is a critical target in the development of this emerging photovoltaic material. Metal oxide ETL/Sb2Se3 device performance has historically been limited by relatively low fill factors, despite offering clear advantages with regards to photocurrent collection. In this study, TiO2 ETLs are fabricated via direct current reactive sputtering and tested in complete Sb2Se3 devices. A strong correlation between TiO2 ETL processing conditions and the Sb2Se3 solar cell device response under forward bias conditions is observed and optimized. Numerical device models support experimental evidence of a spike‐like conduction band offset, which can be mediated, provided a sufficiently high conductivity and low interfacial defect density can be achieved in the TiO2 ETL. Ultimately, a SnO2:F/TiO2/Sb2Se3/P3HT/Au device with the reactively sputtered TiO2 ETL delivers an 8.12% power conversion efficiency (η), the highest TiO2/Sb2Se3 device reported to‐date. This is achieved by a substantial reduction in series resistance, driven by improved crystallinity of the reactively sputtered anatase‐TiO2 ETL, whilst maintaining almost maximum current collection for this device architecture. [ABSTRACT FROM AUTHOR]

The hydrothermal technique (90°C, 6 h) was used in this study to generate negatively conductive zinc oxide (ZnO) nanorods (NRs) on silver (Ag) nucleation layers, which have been deposited on glass substrate through DC magnetron sputtering and had average thicknesses ranging from 150 nm to 1500 nm. The properties that were studied were optical, structural, and electrical. ZnO NR films were all polycrystalline, according to structural measurements, and (002) plane exhibited the dominant reflection. ZnO NRs' reflection intensity reduced as the thickness regarding Ag nucleation layer increased, suggesting a reduction in the crystallization intensity. Surface measurements demonstrated that there was a discernible change in the nanostructures' shape as the thickness of the Ag nucleation layer increased. The nanostructures went from radially spherical configurations to needles, irregular rods, and finally regular hexagonal rods perpendicular to glass substrate's surface. As the thickness of Ag nucleation layer rose, optical tests revealed a drop in transmittance and an increase in optical energy gap values, while Hall measurements revealed an increase in the concentration of hole charge carriers from 8.755 1017 cm-3 to 12.788 1017 cm-3. [ABSTRACT FROM AUTHOR]

Thin films are the backbone of the electronics industry, and their widespread application in heat sensors, solar cells, and thin-film transistors has attracted the attention of researchers. The current study involves the deposition of a hetero-structured (ZnO/Zn/ZnO) thin film on a well-cleaned glass substrate using the DC magnetron sputtering technique. The samples were then annealed at 100, 200, 300, 400, and 500 °C. The structural, morphological, and electrical characteristics of the annealed samples as well as one as-deposited sample were then examined using atomic force microscopy (AFM), scanning electron microscopy (SEM), X-ray diffraction (XRD), and a Hall effect measuring apparatus. XRD analysis showed a hexagonal ZnO crystal structure for the samples annealed at 300 and 400 °C, whereas the samples annealed at 100 and 200 °C showed metallic zinc and hexagonal ZnO, and the crystallinity decreased for the sample annealed at 500 °C with pure hexagonal crystal symmetry. According to the AFM study, as the annealing temperature increases, the average roughness (Ra) decreases. Temperature has an inverse relationship with particle size. The optimal annealing temperature was determined to be 400 °C. Over this temperature range, the average roughness and particle size increased. Similarly, when Ra decreased, the conductivity increased and the resistance decreased. A fundamental difficulty is that the heating of the heterostructure to 400 °C melts the Zn-based intermediate layer, which alters the Zn phase and disrupts the sample homogeneity. [ABSTRACT FROM AUTHOR]

Amorphous carbon (a-C) has promising potential for temperature sensing due to its outstanding properties. In this work, an a-C thin film temperature sensor integrated with the MEMS silicon accelerometer was proposed, and a-C film was deposited on the fixed frame of the accelerometer chip. The a-C film was deposited by DC magnetron sputtering and linear ion beam, respectively. The nanostructures of two types of films were observed by SEM and TEM. The cluster size of sp2 was analyzed by Raman, and the content of sp2 and sp3 of the carbon film was analyzed by XPS. It showed that the DC-sputtered amorphous carbon film, which had a higher sp2 content, had better temperature-sensitive properties. Then, an integrated sensor chip was designed, and the structure of the accelerometer was simulated and optimized to determine the final sizes. The temperature sensor module had a sensitivity of 1.62 mV/°C at the input voltage of 5 V with a linearity of 0.9958 in the temperature range of 20~150 °C. The sensitivity of the sensor is slightly higher than that of traditional metal film temperature sensors. The accelerometer module had a sensitivity of 1.4 mV/g/5 V, a nonlinearity of 0.38%, a repeatability of 1.56%, a total thermomechanical noise of 509 μg over the range of 1 to 20 Hz, and an average thermomechanical noise density of 116 µg/√Hz, which is smaller than the input acceleration amplitude for testing sensitivity. Under different temperatures, the performance of the accelerometer was tested. This research provided significant insights into the convenient procedure to develop a high-performance, economical temperature–accelerometer-integrated MEMS sensor. [ABSTRACT FROM AUTHOR]

Steel surface protection with hard coatings is essential in metalworking, yet developing high-performance coatings is challenging. TiAlSiN coatings grown on various substrates using commercial targets have been extensively studied, but consistent data on their properties are lacking. This study focused on TiAlSiN single layers (SL) and TiAlSiN/TiN bilayers (BL), with an 800 nm thick TiAlSiN top layer and a 100 nm thick TiN mid layer. These coatings were grown on C120 tool steel discs via reactive DC magnetron sputtering using TiAlSi 75–20–5 at.% and Ti targets fabricated in-house through spark plasma sintering. The stability of coatings was assessed after thermal treatment (TT) in air at 800 °C for 1 h. SEM analysis revealed a columnar microstructure with pyramidal grains in the SL and BL coatings, and coarser pyramidal and prismatic grains in both TT coatings. EDS analysis showed a decrease in Ti, Al, Si, and N content after annealing, while O content increased due to oxide formation. High indentation hardness (9.19 ± 0.09 GPa) and low effective elastic modulus (148 ± 6 GPa) were displayed by the BL TT coating, indicating good resistance to plastic deformation and better load distribution. The highest fracture toughness was noted in the BL TT coating (0.0354 GPa), which was 16.4 times greater than the steel substrate. Better scratch resistance and low coefficient of friction (COF ≤ 0.35) were exhibited by both TT coatings. Tribological tests showed a mean COF of 0.616–0.773, comparable to the steel substrate (0.670). The lowest corrosion current density (0.1298 µA/cm²), highest polarization resistance (46.34 kΩ cm²), and a reduced corrosion rate (1.51 µm/year) in a 3.5 wt.% NaCl solution was also exhibited by the BL TT coating. These findings indicate TiAlSiN/TiN films as effective protective coatings for tool steel surfaces. [ABSTRACT FROM AUTHOR]

This research aimed to investigate the effects of input power and gas flow rate on the composition, microstructure, and mechanical properties of TiZrHfNiCuCo metallic coatings. These metallic coatings were deposited on a p-type Si wafer using a direct current magnetron sputtering system with varying input powers (100–300 W) and Ar flow rates (5–20 sccm). It was observed that increasing input power and decreasing Ar flow rate led to TiZrHfNiCuCo metallic coatings with higher hardness and smoother surfaces. The experiment resulted in the formation of a metallic amorphous coating. This study describes the mechanism by which the mechanical properties of the TiZrHfNiCuCo coating change according to sputtering parameters. Based on these results, the effects of sputter variables, such as input power and gas flow rate properties, on the properties of coatings are discussed. [ABSTRACT FROM AUTHOR]

Niobium oxide thin films were grown on both rigid and flexible substrates using DC magnetron sputtering for electrochromic applications. Three experimental series were conducted, varying the oxygen to argon flow rate ratio and deposition time. In the first series, the oxygen to argon ratio was adjusted from 0 to 0.32 while maintaining a constant growth time of 30 min. For the second and third series, the oxygen to argon ratios were fixed at 0.40 and 0.56, respectively, with deposition times ranging from 15 to 60 min. A structural transition from crystalline to amorphous was observed at an oxygen to argon flow rate ratio of 0.32. This transition coincided with a change in appearance, from non-transparent with metallic-like electrical conductivity to transparent with dielectric behavior. The transparent niobium oxide films exhibited thicknesses between 51 nm and 198 nm, with a compact, dense, and featureless morphology, as evidenced by both top-view and cross-sectional images. Films deposited on flexible indium tin oxide (ITO)-coated polyethylene terephthalate (PET) substrates displayed a maximum surface roughness (Sq) of 9 nm and a maximum optical transmission of 83% in the visible range. The electrochromic response of niobium oxide thin films on ITO-coated PET substrates demonstrated a maximum coloration efficiency of 30 cm2 C−1 and a reversibility of 96%. Mechanical performance was assessed through bending tests. The ITO-coated PET substrate exhibited a critical bending radius of 6.5 mm. Upon the addition of the niobium oxide layer, this decreased to 5 mm. Electrical resistance measurements indicated that the niobium oxide film mitigated rapid mechanical degradation of the underlying ITO electrode beyond the critical bending radius. [ABSTRACT FROM AUTHOR]

This study investigates the influence of Cu thickness ratios on the structural, morphological, and mechanical properties of sputtered Cu–W and Cu–Cr bilayer thin films. Employing high power impulse magnetron sputtering (HiPIMS), five distinct thickness ratios of 1:3, 3:5, 1:1, 5:3, and 3:1 were analyzed and compared to bilayer films developed using direct current magnetron sputtering (DCMS). The microstructural and surface characteristics of these films were evaluated using x-ray diffraction (XRD), atomic force microscopy, and scanning electron microscopy. Electrical properties were measured using a four-point probe, while mechanical properties were assessed through nanoindentation. Results reveal that increasing Cu thickness in Cu–W and Cu–Cr bilayers inversely affects hardness, grain size, and roughness, highlighting the influence of thickness ratios on film properties. Films with a higher Cu thickness ratio in both Cu–W and Cu–Cr bilayer systems deposited by HiPIMS exhibited lower hardness, smaller grain size, and reduced average roughness. Cross-sectional analysis and XRD confirmed the impact of thickness ratio on crystal phase and microstructure, indicating smoother columnar structures. Specifically, the HiPIMS-deposited Cu–Cr 3-1 film exhibited the lowest resistivity, at 4.77 μΩ cm, and hardness, measuring 8.26 GPa. Moreover, the 1:1 ratio films of Cu–W and Cu–Cr demonstrated hardness values of 13.81 and 11.37 GPa, respectively, which were 1.39 times higher than the films grown by DCMS. Additionally, variations in the bilayer thickness ratio significantly affected the electrical properties of the films. The enhanced properties of HiPIMS films are attributed to the higher peak power density of the target, leading to increased ion energy and deposition of dense grain structures. [ABSTRACT FROM AUTHOR]

A comparative study on nonreactively direct current magnetron sputtered (DCMS) and high-power pulsed magnetron sputtered (HPPMS) MoSi2-based coatings has been implemented with the objective of advancing the knowledge on the growth conditions and oxidation resistance of MoSi2 thin films. The energy supplied during the growth process (i.e., deposition temperature and ionization degree) exerts a significant influence on the phase formation and morphology. At 200 °C, highly dense but x-ray amorphous films are prevalent, whereas an increase up to 400 °C leads to dense and fine-columnar structured hexagonal MoSi2 films. Increased growth temperatures (≥500 °C for DCMS) and strongly ionized plasma states result in the formation of dual-phase structures (h-MoSi2 and t-Mo5Si3), accompanied by slightly underdense but strongly columnar grains. The MoSi1.92 HPPMS film (1000 Hz, 10% duty cycle) grown at 500 °C exhibits the maximum hardness of 22.8 GPa and an elastic modulus of approximately 400 GPa. In long-term oxidation tests conducted at 600, 850, and 1200 °C (up to 100 h), all MoSi2-based films exhibited a temperature-dependent scale formation. Up to 850 °C, the formation of a continuous, dense protective scale is disrupted by the competing growth of MoOx and SiOx. At temperatures exceeding 1200 °C, all MoSi2-based coatings analyzed demonstrate exceptional oxidation resistance, resulting in the formation of a continuous, dense SiO2 scale. At 1500 °C for 30 min, the initially slightly underdense and dual-phased MoSi1.92 coating achieved a scale thickness of only 670 nm, thereby demonstrating the exceptional oxidation resistance capabilities of HPPMS-grown MoSi2-based coatings. [ABSTRACT FROM AUTHOR]

Cr-Ni3Al alloy films have been deposited on Si (100) substrate via DC magnetron sputtering. The effect of Cr enrichment on microstructure and mechanical properties has been studied. The evolution of phases, microstructure, surface topography and mechanical properties has been studied using GI-XRD, FE-SEM, AFM and quasi-static nanoindentation, respectively. Results revealed that the alloy films possessed a preferred orientation of (111) plane with a maximum hardness and Young's modulus of ~ 12.7 GPa and ~ 203 GPa for 0 W Cr-Ni3Al films which further decreased to ~ 7 GPa and 129 GPa, respectively, for 40 W Cr-Ni3Al films. The reported values of hardness and Young's modulus are very high in the case of alloy Ni3Al-based coatings when compared with the literature. This study also imitates that with the increase in Cr concentration in the host Ni3Al matrix, the surface roughness increased as a result of the evolution of pores. However, hydrophobicity is observed to be increased with increase in Cr concentration in host Ni3Al coatings with a maximum contact angle of 115.9° for 40 W Cr-Ni3Al alloy film. [ABSTRACT FROM AUTHOR]

Ni3Al and Cr-Ni3Al films were deposited on Inconel-718 using the DC magnetron sputtering at a substrate temperature of 400 °C. The evolution of phase, microstructure, surface topography, and mechanical properties of the deposited films have been characterized using XRD, FESEM, AFM, and nanoindentation, respectively. The results of nanoindentation showed that the hardness, modulus, and adhesive strength of the coatings increased with increase in Cr concentration in the host Ni3Al matrix. The maximum hardness and modulus of 10.62 and 150.42 GPa respectively are shown by 5.7 at% of Cr-Ni3Al films. The cyclic oxidation tests were performed at elevated temperatures of 900 °C, 1000 °C, and 1100 °C in the open-air environment to study the actual oxidation attack. The results of the test showed that the rate of oxidation in Ni3Al and Cr-Ni3Al films was low as compared to the uncoated substrate. Ni3Al film doped with 5.7 at% of Cr-Ni3Al has resulted in providing better protection to the substrate against oxidation attacks. The surface morphology and elemental composition of the oxidized samples were investigated using FESEM and EDS to elucidate the surface scale analysis and mechanism of oxidation due to the formation of different oxide layers. [ABSTRACT FROM AUTHOR]

Austenitic stainless steel (ASS) and duplex stainless steel (DSS) are referred as "difficult-to-cut" materials in the manufacturing industry because of different machining difficulties including work hardening, high cutting temperatures and formation of built-up layers. DSS is the preferred replacement for ASS but includes a difficult manufacturing environment. Moreover, the wet machining conditions raise several issues related to the human health, environment, disposition and costing. However, turning of these materials in the dry environment is a challenging task. The present research work is a comparison of machinability aspects of ASS 304 and DSS 2205 in a dry environment using AlTiN coating deposited by two advanced coating deposition techniques including direct current magnetron sputtering (DCMS) and high-power impulse magnetron sputtering (HiPIMS). Uncoated tools showed the worst performance at every stage of machining. AlTiN (HiPIMS)-coated tools showed the lowest increase in average surface roughness of 8%, 17% lower cutting force and 1.5-times higher tool life compared to AlTiN (DCMS) tools. DSS 2205 was the most difficult material to machine in dry conditions, exhibiting the lowest average tool life of 3890 mm compared to 4315 mm by ASS 304. Moreover, HiPIMS-coated tools helped in improving the machining performance of DSS 2205 up to some extent. [ABSTRACT FROM AUTHOR]

CrN and diamond-like carbon (DLC) coatings are deposited on the surface of 431 stainless steel by the direct current magnetron sputtering technique. The surface morphology, micro-structure, hardness, friction, and wear properties of CrN, CrN/DLC and multi-layer composite DLC coatings are investigated by scanning electron microscopy, X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, nanoindentation tester, scratch tester, and friction and wear tester. The results show that the surface of the single CrN coating is very rough for the columnar crystal structure with preferred orientation. When it serves as inner transition layers to form the composite DLC coatings, the surface gets much smoother, with reduced defects. The friction and wear results indicate that the composite DLC coatings exhibit lower coefficients of friction, and better wear and corrosion resistance in dry friction, deionized water, and seawater. In the dry wear and friction process, the single CrN coating is easily worn out, and severe friction oxidation and furrow wear both appear with a friction coefficient of 0.48. But the friction coefficient of a CrN coating in seawater is reduced to 0.16, and friction oxidation and wear loss are further reduced with water lubrication. The CrN/DLC coating has excellent tribological performance in three test concoctions and has the lowest friction coefficient of 0.08 in seawater, which is related to the higher sp3 bond content, density (1.907 g/cm3) and high degree of amorphization, contributing to high hardness and a self-lubrication effect. However, due to the limited thickness of CrN/DLC (1.14 µm), it easily peels off and fails during friction and wear in different testing conditions. In multi-layer composite DLC coatings, there are more sp2 bonds with decreased amorphization, high enough thickness (4.02 µm), and increased bonding strength for the formation of different carbides and nitrides of chromium as transition layers, which gives rise to the further decreased average friction coefficient and the lowest wear loss. Therefore, the CrN coating alone has good wear resistance, and, as with the inner transition layer with a DLC coating, it can effectively improve the overall thickness and the bonding strength of the multi-layer films by optimizing the chemical compounds of DLC coatings. These results provide experimental support and reference for the design and selection of surface coatings for 431 stainless steels in different working conditions. [ABSTRACT FROM AUTHOR]

Vanadium (~450 nm) and V2O5 (~350 nm) were deposited by DC magnetron sputtering on an AM60 substrate to improve its degradation resistance in marine ambience. According to Raman and XPS analysis, the vanadium nanofilm mainly consists of amorphous V 2 O 3 , while V 2 O 5 comprises two sheets of V O 5 and V O 4 units. After 30 days of immersion of the coated AM60 in a marine model solution (SME), the shift of the pH of the SME to more alkaline values was less pronounced for V 2 O 5 -AM60 because of the HCl acid formation during the partial dissolution of V 2 O 5 in the presence of NaCl, and thus, a higher concentration of Mg 2 + ions ~ 100   mg   L - 1 was released from the Mg (AM60) matrix. The lower concentration of ~ 40   mg   L - 1 from the V-AM60 surface was attributed to the possible intercalation of the released Mg ions (cations) into the conductive tunnels of V 2 O 3 as the main component of the vanadium sputtered deposit. This oxide has been reported as a material for high-capacitive energy storage. In this way, the V-deposit provided longer partial protection for the AM60 surface (Mg matrix) from localized pitting attacks. [ABSTRACT FROM AUTHOR]

Nickel oxide (NiO) nanostructure was successfully prepared via reactive DC magnetron sputtering on the soda-lima glass substrate, which can be used for various applications. Xray diffraction (XRD) investigations were used to evaluate NiO with two annealing durations. The results revealed that the deposited films had a cubic structure and polycrystalline nanoparticles. A significant polycrystalline structure could be seen in the sputtered films as a diffraction peak oriented toward NiO (200). Field-emission Scanning Electron Microscopy (FE-SEM) analysis identified the surface morphology of NiO nanoparticles prepared at two different annealing times with the two average sizes (24 and 32 nm) respectively. The samples' roughness was assessed using atomic force microscopy (AFM). Increased annealing time was shown to result in a decrease in grain size. The energy band gap (Eg) expanded with increasing annealing time, according to UV-visible spectroscopy (UV-Vis). FTIR spectroscopy was used to determine the functional groups of NiO nanoparticles and their bonding nature. The results indicate that optical characterizations are more sensitive to the annealing period. [ABSTRACT FROM AUTHOR]

This study examines how the substrate temperature affects the electrical characteristics of the Zr-doped HfO2/Al/Zr-doped HfO2 (HZO/Al/HZO) tri-layer stack. Tri-layer stack is deposited by a simultaneous use of RF magnetron sputtering for HfO2 and DC magnetron sputtering for Zr and Al targets. During deposition, the substrate temperature is varied from 25 to 300°C. The observed hysteresis loop is prominent for the stack deposited at room temperature, while it becomes minute at higher temperatures. Interface trap density and oxide charge density of the tri-layer stack are minimum at 300°C and maximum at room temperatures. Frequency dispersion is detected in the stack deposited at room temperature, but it disappears in stacks deposited at 300°C. In addition, compared to other tri-layer stacks, the stack deposited at 300°C shows good conductivity. Therefore, compared to other samples, the tri-layer stack deposited at 300°C has improved electrical characteristics. It is shown that the substrate temperature has a significant impact on the electrical properties of the stack. [ABSTRACT FROM AUTHOR]

The unique mechanical properties of Tungsten Carbide (WC), such as fracture toughness, exceptional hardness, high melting temperature, outstanding thermal stability, anti-oxidation qualities fatigue and creep resistance, have made it a suitable industrial material for different applications. It is also considered to be a promising material for coating on plasma-facing walls in a Tokamak reactor. The aim of the present work is to study the effect of varying substrate temperature, concentration of tungsten (W) and annealing in the structural properties of WC films. The WC films are deposited on a silicon substrate at different substrate temperatures viz. RT (300 K), 400, 500, 600 and 700 K using DC magnetron sputtering. W-rich WC films were deposited keeping the power of WC constant (100 Watt) and varying W powers (10 Watt, 20 Watt, 30 Watt, 40 Watt) at room temperature. Later, these W-rich WC films were annealed at 800°C in a reducing atmosphere. Glancing incidence X-ray diffraction (GIXRD) and Raman spectroscopy of the films are performed for structural analysis. GIXRD of the WC films reveals that as-deposited RT films are amorphous. However, films which are either deposited at elevated substrate temperature or are annealed are crystalline. This is confirmed by Raman's measurements. It also indicates the presence of disorder and nanocrystalline phases due to temperature variations. [ABSTRACT FROM AUTHOR]

Ni3Al films were deposited on silicon (100) substrate at different substrate temperatures by DC magnetron sputtering. The evolution of phase, microstructure, surface topography and mechanical properties have been investigated as a function of substrate temperature via XRD, FE-SEM, AFM and nanoindentation respectively. Results revealed that the deposited film possessed the preferred orientation of (111) whereas the crystallite size increased and grain size decreased with increase in the substrate temperature. The results of nanoindentation showed that the hardness of the film increased up to 400 °C after which it abruptly decreased. Maximum hardness of ∼13 GPa was achieved when the film was deposited at the substrate temperature of 400 °C. The surface roughness of the film increases simultaneously with the increase in substrate temperature whereas the static contact angle and mechanical properties declined significantly for the film deposited at the substrate temperature of 600 °C. This study reflects the impact of substrate temperature on the evolution of phase, microstructure and mechanical properties of Ni3Al coatings deposited at different substrate temperatures. [ABSTRACT FROM AUTHOR]

Cu3N films are investigated utilizing direct current magnetron sputtering from the Cu target in an Ar/N2 mixed sputtering gas. X-ray diffractive analysis, Ultra-violet absorption spectroscopy, X-ray dispersive spectroscopy, atomic force microscopy, field-emission scanning electron microscopy, Hall measurements, and I–V characteristic measurements are used to investigate the properties of the films. The study findings initially obtained films with a Cu3N composition at the appropriate substrate temperature of 80 °C. When the N2:(Ar + N2) gas ratio is more than 50%, the electrical property of films switches from n-type to p-type. The film obtains the greatest crystal quality and the best p-type electric property at the N2:(Ar + N2) gas ratio of 70%, with resistivity, hole concentration, and hole mobility of 1.18 × 10–2 Ωcm, 9.8 × 1019 cm−3, and 5.4 cm2V−1 s−1, respectively. A p–n Cu3N homojunction cell has an efficiency of 0.21%. [ABSTRACT FROM AUTHOR]

Self-assembled gold and silver nanoparticles were fabricated in medium vacuum conditions on Corning glass substrates by means of DC magnetron sputtering. The samples were deposited either at 420 °C or 440 °C, or they were initially deposited at room temperature followed by post annealing. Subsequently, they were covered with three different polymers, namely Polystyrene-block-polybutadiene-blockpolystyrene (PS-b-PBD-b-PS), Polystyrene-co-methyl methacrylate (PS-co-PMMA) and Polystyreneblock-polyisoprene-block-polystyrene (PS-b-PI-b-PS), using spin coating. Localized surface plasmon resonances were recorded in the temperature range of −25 °C–100 °C. We show that the resonance position changes systematically as a function of temperature. Theoretical calculations carried out via the Rigorous Coupled Wave Analysis support the experimental results. Based on these findings, the investigated materials demonstrate potential as components for the development of temperature sensors. [ABSTRACT FROM AUTHOR]

PVD Sputtering is a very popular, and versatile coating method to create multi-functionalities on various kinds of substrates including textile surfaces. The paper presents the obtaining of the two conductive textile structures via the hybrid PVD by DC sputtering method with copper target and analysis of them from the structural and electrical properties point of view. The two textile substrates are woven, made of 100% cotton yarns, with a specific mass of 207 g/m2 that was preliminary prepared by chemical finishing (padding) with two different substances: ITOBINDER-Acrilat (TA1) si PERMUTEX-EX-RU-Urethan (TA2). After the sputtering process a Cu thin layer with a specific mass of about 5 mg/cm2were obtained. The SEM analyses revealed a fibrous structure, on the surface of which a thin coating has been deposited. It is found that the coating has a columnar appearance and is uniform and continuous on the surface of the sample. The electric measurements were made with BX PRECISION 889B Bench LRC/ESR METER. on 1 inch and 10 cm show that the electrical conductivity values are up to 83% higher for the textile samples preliminary finished with TA1 than those with TA2 and decrease with increasing distance between electrodes. [ABSTRACT FROM AUTHOR]

We fabricate superconducting quantum interference devices (SQUIDs) made of niobium-titanium nitride (NbTiN) thin films on the apex of sharp quartz capillaries. By incorporating reactive DC magnetron sputtering into the self-aligned deposition process for the SQUID-on-tip (SOT) fabrication, we produce NbTiN SOT devices with an effective diameter of ∼100 nm. The ø110 nm device has a superconducting transition temperature of 13.2 K, magnetic flux noise down to 0.7 μ Φ 0 / Hz0.5 (4 K), and operating temperatures of 1.8–10 K. The developed technique enables the synthesis of nitride and other superconductors, thereby expanding the range of materials available for SOT devices. [ABSTRACT FROM AUTHOR]

Cr coatings were deposited on both the polished and rough substrate using DC magnetron sputtering. The influence of substrate surface roughness on the morphology, crystalline phase and mechanical properties of the coatings were analyzed. The results showed that surface roughness had a significant effect on the surface morphology of the coating, as the coating inherited the surface morphology of the substrate. Surface roughness before and after coating for the polished and rough surfaces were 0.054–0.046 and 0.107–0.563μm, respectively. The hardness and Young’s modulus of the coating deposited on the polished surface were 5.5 and 188.6GPa, respectively, while the mechanical properties of the coating deposited on the rough surface are about the same. The results showed that the adhesion of the coating can be improved by appropriately increasing the surface roughness. [ABSTRACT FROM AUTHOR]

This work uses the direct current magnetron sputtering (DCMS) of equi-atomic (AlTiZrHfTa) and Si targets in dynamic sweep mode to deposit nano-layered (AlTiZrHfTa)Nx/SiNx refractory high-entropy coatings (RHECs). Transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) are used to investigate the effect of Si addition on the oxidation behavior of the nano-layered coatings. The Si-free nitride coating exhibits FCC structure and columnar morphology, while the Si-doped nitride coatings present a FCC (AlTiZrHfTa)N/amorphous-SiNx nano-layered architecture. The hardness decreases from 24.3 ± 1.0 GPa to 17.5 ± 1.0 GPa because of the nano-layered architecture, whilst Young's modulus reduces from 188.0 ± 1.0 GPa to roughly 162.4 ± 1.0 GPa. By increasing the thickness of the SiNx nano-layer, kp values decrease significantly from 3.36 × 10−8 g2 cm−4 h−1 to 6.06 × 10−9 g2 cm−4 h−1. The activation energy increases from 90.8 kJ·mol−1 for (AlTiZrHfTa)Nx nitride coating to 126.52 kJ·mol−1 for the (AlTiZrHfTa)Nx/SiNx nano-layered coating. The formation of a FCC (AlTiZrHfTa)-Nx/a-SiNx nano-layered architecture results in the improvement of the resistance to oxidation at high temperature. [ABSTRACT FROM AUTHOR]

This research reports the development of 3D carbon nanostructures that can provide unique capabilities for manufacturing carbon nanotube (CNT) electronic components, electrochemical probes, biosensors, and tissue scaffolds. The shaped CNT arrays were grown on patterned catalytic substrate by chemical vapor deposition (CVD) method. The new fabrication process for catalyst patterning based on combination of nanoimprint lithography (NIL), magnetron sputtering, and reactive etching techniques was studied. The optimal process parameters for each technique were evaluated. The catalyst was made by deposition of Fe and Co nanoparticles over an alumina support layer on a Si/SiO2 substrate. The metal particles were deposited using direct current (DC) magnetron sputtering technique, with a particle ranging from 6 nm to 12 nm and density from 70 to 1000 particles/micron. The Alumina layer was deposited by radio frequency (RF) and reactive pulsed DC sputtering, and the effect of sputtering parameters on surface roughness was studied. The pattern was developed by thermal NIL using Si master-molds with PMMA and NRX1025 polymers as thermal resists. Catalyst patterns of lines, dots, and holes ranging from 70 nm to 500 nm were produced and characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Vertically aligned CNTs were successfully grown on patterned catalyst and their quality was evaluated by SEM and micro-Raman. The results confirm that the new fabrication process has the ability to control the size and shape of CNT arrays with superior quality. [ABSTRACT FROM AUTHOR]

Biocompatibility and tribological issues with 316L stainless steel (SS) biomaterials reduce their service life. A metallic substrate made of stainless steel 316L (SS) was employed. After being subjected to a surface anodization process using sulfuric and nitric acids, it was coated with silver using a DC sputtering plasma method. The coating's crystallinity, morphology, and microstructure have been investigated using structural characterization methods such as XRD, FESEM, and EDS. To assess the coatings' qualitative adherence to the steel substrates, the coated substrates underwent the Rockwell - C indentation tests. An optical profilometer was used to measure the coatings' surface properties. The corrosion resistance of coated and uncoated SS substrates was evaluated using potentio-dynamic polarization experiments. The results show that the silver coating and anodized surface increase SS's resistance to corrosion behavior. The silver-coated SS and surfaces treated for corrosion both see a reduction in the current density of corrosion. These further demonstrate the potential for using surface-treated and silvercoated stainless steel as a surgical instrument to increase biocompatibility and resistance to corrosion. [ABSTRACT FROM AUTHOR]

The composition, structure and mechanical properties of Ti–Al–Ta–N coatings obtained by high-power impulse magnetron sputtering and direct current magnetron sputtering have been studied using energy-dispersive X-ray spectroscopy, X-ray diffraction, scanning electron microscopy, and nanoindentation. It has been established that for high-power impulse sputtering, the current and power of the magnetron discharge increase exponentially during the pulse and reach peak values that are an order of magnitude higher than similar characteristics for magnetron sputtering at direct current. A high level of ionization of the sputtered particles caused a significant increase in the number of ions in the particle flux deposited on the substrate. The suppression of the growth of columnar grains and the formation of a denser and more homogeneous microstructure were ensured by an increase in the intensity of ion bombardment of the growing coating. This made it possible to improve its mechanical characteristics. [ABSTRACT FROM AUTHOR]

The performance of next-generation particle accelerators has been adversely affected by the occurrence of electron multipacting and vacuum instabilities. Particularly, minimization of secondary electron emission (SEE) and reduction of surface resistance are two critical issues to prevent some of the phenomena such as beam instability, reduction of beam lifetime, and residual gas ionization, all of which occur as a result of these adverse effects in next-generation particle accelerators. For the first time, novel quinary alloy Ti–Zr–V–Hf–Cu non-evaporable getter (NEG) films were prepared on stainless steel substrates by using the direct current magnetron sputtering technique to reduce surface resistance and SEE yield with an efficient pumping performance. Based on the experimental findings, the surface resistance of the quinary Ti–Zr–V–Hf–Cu NEG films was established to be 6.6 × 10−7 Ω m for sample no. 1, 6.4 × 10−7 Ω m for sample no. 2, and 6.2 × 10−7 Ω m for sample no. 3. The δmax measurements recorded for Ti–Zr–V–Hf–Cu NEG films are 1.33 for sample no. 1, 1.34 for sample no. 2, and 1.35 for sample no. 3. Upon heating the Ti–Zr–V–Hf–Cu NEG film to 150 °C, the XPS spectra results indicated that there are significant changes in the chemical states of its constituent metals, Ti, Zr, V, Hf, and Cu, and these chemical state changes continued with heating at 180 °C. This implies that upon heating at 150 °C, the Ti–Zr–V–Hf–Cu NEG film becomes activated, showing that novel quinary NEG films can be effectively employed as getter pumps for generating ultra-high vacuum conditions. [ABSTRACT FROM AUTHOR]

High-throughput methods are extremely important in today's materials science, especially in the case of thin film characterization. The micro-combinatorial method enables the deposition and characterization of entire multicomponent thin film systems within a single sample. In this paper, we report the application of this method for the comprehensive TEM characterization of the Y-Ti-O layer system. Variable composition samples (YxTi1−xOy) were prepared by dual DC magnetron sputtering, covering the entire (0 ≤ x ≤ 1) concentration range. The structure and morphology of phases formed in both as-deposited and annealed samples at 600, 700, and 800 °C were revealed as a function of Y-Ti composition (x). A comprehensive map showing the appropriate amorphous and crystalline phases, and their occurrence regions of the whole Y-Ti-O layer system, was revealed. Thanks to the applied method, it was shown with ease that at the given experimental conditions, the Y2Ti2O7 phase with a pyrochlore structure forms already at 700 °C without the TiO2 and Y2O3 by-phases, which is remarkably lower than the required temperature for most physical preparation methods, demonstrating the importance and benefits of creating phase maps in materials science and technology. [ABSTRACT FROM AUTHOR]

This article presents the biochemical properties of poly(lactide)-zinc (PLA-Zn) composites obtained by DC magnetron sputtering of zinc onto melt-blown nonwoven fabrics. The biochemical properties were determined by the evaluation of the activated partial thromboplastin time (aPTT) and prothrombin time (PT). The antimicrobial activity of the PLA-Zn samples was additionally tested against representative Gram-positive and Gram-negative bacteria strains. A structural study of the PLA-Zn has been carried out using specific surface area and total pore volume (BET) analysis, as well as atomic absorption spectrometry with flame excitation (FAAS). PLA-Zn composites exhibited an antibacterial effect against the analyzed strains and produced inhibition zones against E. coli and S. aureus. Biochemical investigations revealed that the untreated PLA fibers caused the acceleration of the clotting of human blood plasma in the intrinsic pathway. However, the PLA-Zn composites demonstrated significantly different properties in this regard, the aPTT was prolonged while the PT was not altered. [ABSTRACT FROM AUTHOR]

High-quality W, Mo, Ti, Zr, and Ga-doped indium oxide (multiple-doped In2O3) films are deposited at room temperature by direct current magnetron sputtering process under different oxygen proportion, with 200 °C annealing. A maximum Hall mobility of 71.6 cm2 V−1 s−1 is obtained at a middle oxygen proportion of 2%, thanks to the reduction of impurity scattering center, which is nearly three times higher than an ITO film of 23.6 cm2 V−1 s−1. The multiple-doped In2O3 films showed a remarkable 30% improvement of the optical transmittance (>80%) in the near-infrared (NIR) region compared to the ITO film (about 60%), which is mainly attributed to the decrement of free carrier absorption due to low carrier concentration (<2 × 1020 cm−3), an order magnitude lower than the ITO film (1.56 × 1021 cm−3). Additionally, x-ray diffraction results confirm that the films have a polycrystalline structure with preferential orientation growth in the <100> direction. In the NIR region, the multiple-doped In2O3 films have a superior figure of merit of 5.02 × 10−3 Ω−1, which is an order magnitude higher than the ITO film (5.31 × 10−4 Ω−1). This work reports a new In2O3-based material with both high electrical and optical performance, which is suitable for the application of advanced optoelectronic devices. [ABSTRACT FROM AUTHOR]

The direct impact of structural quality on the ferroelectric properties of hexagonal Al1–xScxN with an Sc-content of x = 0.3 was investigated using dynamic hysteresis measurements, high-resolution x-ray diffraction (HRXRD), and atomic force microscopy. The films investigated were deposited on p-doped (001)-Si substrates by reactive pulsed DC magnetron sputtering under different gas mixtures to vary the structural quality and surface morphology between samples. Misoriented grains were identified as ferroelectrically inactive, as these grains resulted in an underestimation and distortion of the ferroelectric quantities. In fact, a high amount of misoriented volume was found to have a significant effect on the coercive electric field, as this is mainly determined by the crystal strain in the ferroelectric [0001]-oriented regions, independent of its origin. Furthermore, it was concluded that the crystal quality does not have a pronounced effect on the coercive field strength. Conversely, the polarization in the film is mainly determined by the crystal quality, as a difference of 1° in the HRXRD FWHM of the ω-scan resulted in a 60% loss of polarization. The amount of polarization was influenced to a lesser extent by the misoriented grains since the ferroelectric volume of the layers was only slightly overestimated. This reveals that optimizing reproducible and transferable properties, such as crystal quality and surface morphology, is more reasonable, as the film with the lowest misoriented volume and the highest degree of c-axis orientation showed the highest polarization. [ABSTRACT FROM AUTHOR]