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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.

Glow discharges are known to be limited for running at high currents (−2). Magnetically enhanced plasmas could overcome this limitation, typically for the magnetron operated in pulsed mode during a few 100μs. Hence, the current density could be increased by two decades, but it still stays below 10 A · cm−2. Here we report on a long (∼1 ms) pulsed operation of magnetrons, while preserving the glow mode, for current densities exceeding at least 3 times the highest current density reported for high power pulsed magnetrons. Even if the density of energy surpasses 7 J · cm−2, no arc transition was observed. Three target materials have been successfully tested: carbon (C), molybdenum (Mo) and tungsten (W) in helium atmosphere, from 5 to 30 Pa. Two key parameters are required to reach the Hyper Power Impulse Magnetron (HyPIM) glow mode: i) the accurate control of the maximum voltage during the pulse and ii) the use of the pre-ionization. Operating conditions of HyPIM will be presented and compared to other discharges.

We report the amorphous quaternary oxide, indium-tin-silicon-oxide (ITSO), thin film as a new electron-transport layer (ETL) for perovskite solar cells (PSCs). ITSO thin films are grown by magnetron co-sputtering indium-tin-oxide (ITO) and silicon oxide (SiO2) on commercial transparent conducting oxide (ITO) thin films at room temperature. As Si content increases (0–53.8 at%) the optical bandgap increases by over 1.5 eV and the electrical resistivity increases by six orders mainly because of the carrier concentration decrease. Consequently, the ITSO electronic structure depends largely on Si content. PSCs employing ITSO thin films as ETLs were fabricated to evaluate the effect of Si content on device performances. Si content influenced the shunt and series resistance. The optimized device was obtained using an ITSO film with 33.0 at% Si content, exhibiting 14.50% power-conversion efficiency. These results demonstrate that ITSO films are promising for developing efficient PSCs by optimizing the growing process and/or In/Sn/Si/O compositions. This approach can reduce PSC manufacturing process time and costs if ITO and ITSO are grown together by continuous sequential sputtering in a dual gun (ITO and SiO2) chamber.

Heating uniformity inside materials, as a concerned issue of microwave processing, influences essentially the energy utilization of microwave equipment and desired quality of the final product. For the microwave drying of granular materials like germinated brown rice (GBR) on a turntable in microwave ovens, the mode and route of microwave transmission considering sample rotation and the existence of pores inside GBR stacked bulk were investigated, and further to analyze the heating uniformity. The developed physics-based model and simulation strategy can describe microwave drying of GBR stacked bulk. The edge diffraction and uneven surface reflection for the stacked bulk of GBR dominates the transmission of microwaves. Under the fixed magnetron arrangement, same microwave input power, and geometry shape of the sample, the absorption of microwave energy inside GBR stacked bulk mainly relies on the changes in dielectric properties of materials other than those of the electric field. The absorption of microwave energy in GBR stacked bulk greatly dominates the uniformity of temperature distribution. Rotation improves the uniformity of temperature distribution along with equatorial other than radial direction for GBR stacked bulk on a turntable under microwave drying. Sensitivity analysis indicated that increasing rotating speed of the sample has little effect on the heating uniformity as beyond a certain value of 5 circles per minute, and a low bed porosity for GBR stacked bulk relatively improve the heating uniformity, but temperature uniformity is relatively not sensitive to the capillary diffusivity. Research results may enhance understanding of the interaction between microwaves and the stacked bulk of granular materials like GBR with porosity.

This paper presents a Gas Injection Magnetron Sputtering technique as a target temperature-controlling method. This technique is based on the generation of discrete plasmoids by injecting gas into the inter-electrode region. It provides control over the target temperature with limited heat dissipation by using various frequencies of plasma pulse generation. TiN and TiO2 coatings were selected as test materials for the study. Reactive sputtering processes with limited capability to cool the titanium target were carried out by generating a series of 500-ms plasma pulses at frequencies ranging from 0.5 to 1 Hz. The process variants allowed to achieve target temperatures ranging from 720 to 1210 °C. The results of structural, chemical and phase composition studies showed that the temperature of the target sputtering process did not influence the coatings' chemical and phase state. We have observed slight differences in the structure of TiO2 with the temperature since it is a material with a lower melting temperature than TiN. The differences in the thickness of fabricated coatings have been determined. In all the hot sputtering process cases, the deposited layers’ thickness was increased compared to the cold process. The growth kinetics normalized to the power effectivity decreases with the temperature due to the poisoning of the target material.

The effect of nitrogen content on the structural, mechanical and corrosion properties of titanium nitride (TixN1−x) coatings deposited by high power impulse magnetron sputtering (HiPIMS) is investigated. The XRD results showed a (1 1 1) oriented crystalline structure at low nitrogen flow rate Qv(N2), and a mixed (1 1 1) and (2 0 0) at high Qv(N2). The average grain size was derived from XRD results and was found to increase with increasing N2 flow. The hardness results showed a maximum with variation of nitrogen content. All coatings exhibited excellent protection efficiency in acidic media compared to the uncoated steel samples, with protection efficiency reaching up to 98.9%. For reference, direct current magnetron sputtered (dcMS) coatings were deposited and investigated, confirming the superior performance of the HiPIMS coatings.

The electrical, optical, and magnetic properties of half-Heusler compounds make them novel interesting materials being studied by many groups worldwide. The synthesis of YPdBi, a member of half-Heusler compounds, thin films have been achieved at different deposition temperatures such as 360 °C and 470 °C by employing magnetron co-sputtering technique. XRD examinations have revealed that the film deposited at 360 °C has a slightly larger lattice parameter, 6.82 A, than the film fabricated at 470 °C, having 6.73 A. The induced strain of the films has been 2.1% and 0.7% for the films deposited at 360 °C and 470 °C, respectively. X-ray photoelectron spectroscopy (XPS) investigations have revealed the obtained films have the stoichiometry close to the 1:1:1 ratio. Scanning electron microscopy (SEM) studies have shown that surface topography varies dramatically as the deposition temperature advances. Furthermore, high-resolution scanning tunneling electron microscopy (STEM) has shown that layer-plus-island growth known as the Stranski–Krastanov (SK) growth mode, taking place due to minimization of strain energy, leads to the island formation from a specific film thickness on. It has been shown that while the resistance of the samples grown at 470 °C changes abruptly at 2.45 K, which indicates the onset of superconductivity, the sample deposited at 360 °C does not show this effect. The absence of the onset of superconductivity in this latter case might be associated with the lattice strain and intensive scattering in this sample.

In this work, we investigate the hysteresis effect of the current-voltage characteristic for the magnetron sputtered molybdenum disulfide (MoS2) nanocrystalline films. The field emission hysteresis of MoS2 cold cathode is studied by sweeping mode with voltage upward/downward, the vacuum pressure has a remarkable effect on the hysteresis of the emission current and overall the hysteresis becomes more prominent as pressure rises. Besides, we also demonstrate the current-voltage behaviors of MoS2 film using thermal evaporated Al dot as top electrode and copper foil substrate as bottom electrode. The Al/MoS2/Cu configuration device presents an obvious current hysteretic effect and the current increases with the increase of the voltage sweeping times. The possible mechanism of the hysteresis has been proposed herein and also investigations provide a great promise for the development of magnetron sputtered MoS2 nanocrystalline films in applications such as field emitters and memristor devices.

FeCoNiCrMnMox high-entropy alloy (HEA) films were prepared by direct current (DC) magnetron co-sputtering. The influence of the Mo content on the microstructures and mechanical properties of the HEA films were systematically studied by X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), Vickers hardness test and tribological test. The addition of Mo resulted in the formation of a denser film with refined grain size, and promoted the transformation from a face-centered cubic (FCC) phase to a mixture of FCC and body-centered cubic (BCC) phases. The hardness of the films increased from 8.5 GPa (x = 0) to 12 GPa (x = 1) and the friction coefficient decreased from 0.5 (x = 0) to 0.3 (x = 1), which greatly improved the damage tolerance of the film. The improved mechanical and tribological properties of the HEA films is attributed to the formation of hard BCC phase and grain refinement at high content of Mo. The FeCoNiCrMnMox HEA films poise as good protective coatings.

Deposition of alloy films with a well-controlled concentration gradient obtained by co-sputtering from two magnetron sources is studied experimentally and compared with numerical calculations. This method was used together with a linearly moving shutter to fabricate sperimagnetic Co-Tb alloy films with mutually orthogonal concentration and thickness gradients. Using magnetooptical measurements it was demonstrated that, for thicknesses below 10 nm, the compensation concentration (ccomp) shifts towards higher Tb content as the thickness of the Co-Tb film is reduced. Results for Co-Tb alloy films are compared with those for (Tb/Co)RN multilayers with various repetition numbers (RN). For both sample types, the ccomp decreases in a similar way with increasing total film thickness. Thus, the decrease of ccomp with increasing total thickness (either of alloy films or of multilayers) can be considered a universal behavior.

BAlN is a promising ultrawide bandgap semiconductor, but systematic studies of its bandgap are scarce. Here, bandgap engineering of BAlN containing the phase transition factor (from hexagonal to wurtzite structures) has been investigated by DFT calculations and verified experimentally. The calculated bandgap bowing parameter of hexagonal BAlN (h-BAlN) is 2.29 eV, while the bandgap bowing parameters of wurtzite BAlN (w-BAlN) are −4.09 eV and 2.48 eV in the B-rich and Al-rich regions, respectively. Meanwhile, calculations indicate that BAlN preferentially forms w-BAlN at Al composition above 18.7%. So, the bandgap variation of BAlN is divided into three regions based on Al composition: h-BAlN (0–18.7%), B-rich w-BAlN (18.7%–50%), Al-rich w-BAlN (50%–1), and each has its own trend. Experimentally, h-BAlN and w-BAlN films were prepared by magnetron co-sputtering technique and the phase transition was observed in X-ray diffraction (XRD) patterns. h-BAlN shows a typical triangular morphology and the Raman and XRD peaks are located at 1371 cm−1 and 44.3°, tending to (1 0 1) h-BN. w-BAlN has a “needle-felt” surface with Raman and XRD peaks at 656 cm−1 and 35.9°, tending to (0 0 2) w-AlN. The experimental bandgap variation of BAlN shows a “W” shape, which can be well explained by the calculation results.

Preparation of a ternary ReBx–Ti compound within a single magnetron target, forming a plasma surface sintering (PSS) conditions, were investigated. An ionized‑neon pressure of 40 Pa induced sintering power pulses (Ei) with energies of up to 3.1 kJ, which resulted in a low-porosity rhenium boride (3.2%) structure within a solid titanium matrix (ReBx–Ti). The prepared targets showed promising resistance to high temperatures (5.45 mm2/s of thermal diffusivity), after the PSS process at a temperature above 2100 °C. These as-surface-sintered magnetron targets were further used in gas injection magnetron sputtering to obtain Re–B–Ti films characterized by an enhanced deposition rate (120 nm/min). Quantitative analysis of these films revealed that the B/Re ratio was in deficit in comparison to the stoichiometry of as-prepared cathode materials. A multiple-chemical-bond state showed the occurrence of Re B, Ti B, B B, Ti Ti, Ti O, and B O phases, of which TiB2 and ReB2 were dominant, forming therefore a glass-like structure. All gathered data indicated a maximum Vickers microhardness value (36.4 GPa), emphasizing the valuable mechanical response of the deposited Re–B–Ti films, as well as the retaining of their good self-passivation effect, attributed by the oxide phases.

The fabrication of high-hardness non-hydrogenated diamond-like carbon (DLC) via standard magnetron sputtering (MS) is often hindered by the low sputtering yields and ionisation rates of carbon, therefore investigations into pulsed alternatives of MS, else sputtered species post-ionisation methods, are of particular interest. This work focuses on investigating the influence of pulsed-direct current MS (pDCMS), high power impulse magnetron sputtering (HiPIMS) and their microwave plasma-assisted (MA-pDCMS, MA-HiPIMS) variants on the properties of the fabricated DLC films. Two setups were used for the pDCMS- and HiPIMS-based methods, respectively. The films were characterised using Raman spectroscopy, nanoindentation, X-ray reflectometry and scanning electron microscopy, where the pDCMS-produced films were additionally characterised by film-stress measurements. Moreover, in situ time-resolved Langmuir probe plasma analysis was performed under HiPIMS and MA-HiPIMS conditions to analyse the influence of the magnetron and microwave plasmas on one another. For both DCMS- and HiPIMS-based procedures, it was found that the addition of microwave plasma did not facilitate attaining hardnesses beyond 30 GPa, however, it did enable modifying the morphology of the films. Furthermore, this study shows the potential of synchronised sputtering with substrate biasing, as well as the importance of microwave plasma source positioning in relation to the substrate.

Nanocrystalline ZrB2-Ag composite films, which utilize Ag nanoparticles as embedded ions, were directly fabricated via the direct current magnetron co-sputtering technique. Keithley Hall Measuring Instrument allowed insight into the physical features in the temperature of 77 K to 373 K. Ag-containing composite film led to resistivity for composite films descended exponentially rather than linearly, however also resulting in the temperature coefficient of resistivity (TCR) values varied from negative to positive. Both comparable lower resistivity (114.9 μΩ·cm) and even near-zero TCR77-373 K at 3 ppm·K−1 indicated that low resistivity and near-zero temperature drift ZrB2-Ag composite film can be obtained by tailoring the Ag content. Moreover, this provides a promising approach to develop sophisticated thin-film resistors (TFR) materials below and above ambient temperature with a broader temperature range.

Thin film metallic glasses (TFMGs) have attracted great attention due to their excellent functional properties and ease of fabrication as compared with bulk metallic glasses. Among them, TaW-based TFMGs have rarely been studied so far. Here, a novel Ta46.5W35Co18.5 TFMG was successfully developed using a magnetron co-sputtering system. The Ta46.5W35Co18.5 TFMG exhibits high hardness of 12.3 GPa, high elastic modulus of 159 GPa, pronounced plastic deformation behavior, and excellent corrosion resistance, i.e., low passive current density of 7.65 × 10−6 A/cm2 and high corrosion potential of 0.31 V, as well as good thermal stability with high onset crystallization temperature of 1100 K. In addition, the origin of these excellent properties was also investigated in detail by using X-ray diffraction and high-resolution transmission electron microscopy. It was found that, for the Ta46.5W35Co18.5 TFMG, its excellent corrosion resistance may be attributed to the amorphous structure, and the high hardness and good plastic deformation ability are caused by the unique atomic-scale structure with nanocrystals dispersed in the amorphous matrix. This work provides a useful guideline for developing TFMG system combined with excellent corrosion resistance, high hardness, and good thermal stability.

In this work, a super-Nernstian pH sensitivity of TbTaO4 sensing film was developed for an electrolyte-insulator-semiconductor (EIS) solid-state pH sensor. The TbTaO4 sensitive films deposited on the Si substrates through radio-frequency magnetron co-sputtering were prepared under three various Ta plasma powers (80, 120, and 160 W) and then annealed at 800 °C. To investigate the impact of tantalum plasma power, multiple material analyses including X-ray diffraction, secondary ion mass spectrometry, atomic force microscopy, and X-ray photoelectron spectroscopy were performed. Results indicate that the film processed with the 120 W condition might form a stoichiometric TbTaO4 structure and possess a rough surface. Therefore, the best sensing performance was observed for the TbTaO4-based EIS sensor fabricated at the 120 W. In addition, the TbTaO4-based EIS also showed good selectivity for H+ ion over other ions (Na+, K+, Mg2+, and Ca2+). The proposed film fabrication process and analysis may represent a promising approach for the exploration of a novel pH-sensitive TbTaO4 film.