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Chromium Nitride (CrN) coatings have widespread utilization across numerous industrial applications, primarily attributed to their excellent properties. Among the different methods for CrN coating synthesis, direct current magnetron sputtering (DCMS) has been the dominant technique applied. Nonetheless, with the expanded applications of CrN coatings, the need for enhanced mechanical performance is concurrently escalating. High-power impulse magnetron sputtering (HiPIMS), an innovative coating deposition approach developed over the past three decades, is gaining recognition for its capability of yielding coatings with superior mechanical attributes, thereby drawing significant research interest. Considering that the mechanical performance of a coating is fundamentally governed by its microstructural properties, a comprehensive review of CrN coatings fabricated through both techniques is presented. This review of recent literature aims to embark on an insightful comparison between DCMS and HiPIMS, followed by an examination of the microstructure of CrN coatings fabricated via both techniques. Furthermore, the exploration of the underlying factors contributing to the disparities in mechanical properties observed in CrN coatings is revealed. An assessment of the advantages and potential shortcomings of HiPIMS is discussed, offering insight into CrN coating fabrication.

Magnetron sputtering is a very versatile technique extensively employed for the deposition/growth of thin films. However, the deposition of desirable magnetic films is one of the challenges confronting magnetron sputtering owing to the shunting of magnetic flux by magnetic targets in conventional magnetron sputtering equipment. This flux shunting culminates in lower plasma density, non-uniform plasma confinement, and uneven erosion of magnetic targets, adversely affecting the growing films’ thickness uniformity and chemical homogeneity—the latter can be particularly serious in magnetron co-sputtering. In this article, it is discussed that these issues can be avoided by cylindrical sputtering. As for planar sputtering, formerly offered technical solutions including the utilization of thin foils as magnetic targets, the deployment of gapped targets somewhat allowing the magnetic flux of the magnetron assembly, the employment of a target heating system increasing a magnetic target’s temperature greater than or equal to its Curie temperature, facing target sputtering, magnetron sputtering assisted by coupled plasma inductively generated in an internal coil, and the generation of plasma remotely from magnetic targets (i.e., high target utilization sputtering) are scrutinized with their advantages/disadvantages being further examined. Finally, it is discussed that not only can auxiliary grid deployment mitigate/remove the issues of planar magnetron sputtering by modifying spatial plasma density distribution near the target but also it can solely shoulder the responsibility of ionization enhancement and plasma confinement for deposition of magnetic films.

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.

Physical vapour deposition (PVD) is a well-known technology that is widely used for the deposition of thin films regarding many demands, namely tribological behaviour improvement, optical enhancement, visual/esthetic upgrading, and many other fields, with a wide range of applications already being perfectly established. Machining tools are, probably, one of the most common applications of this deposition technique, sometimes used together with chemical vapour deposition (CVD) in order to increase their lifespan, decreasing friction, and improving thermal properties. However, the CVD process is carried out at higher temperatures, inducing higher stresses in the coatings and substrate, being used essentially only when the required coating needs to be deposited using this process. In order to improve this technique, several studies have been carried out optimizing the PVD technique by increasing plasma ionization, decreasing dark areas (zones where there is no deposition into the reactor), improving targets use, enhancing atomic bombardment efficiency, or even increasing the deposition rate and optimizing the selection of gases. These studies reveal a huge potential in changing parameters to improve thin film quality, increasing as well the adhesion to the substrate. However, the process of improving energy efficiency regarding the industrial context has not been studied as deeply as required. This study aims to proceed to a review regarding the improvements already studied in order to optimize the sputtering PVD process, trying to relate these improvements with the industrial requirements as a function of product development and market demand.

This paper validates for the first time the predictive capability of the DYON code for plasma initiation in EAST, which has metallic wall, superconducting coils and conventional tokamak shape, like ITER. The model accurately reproduced the operating spaces of loop voltage and prefill gas pressure for ohmic discharges, demonstrating its validity in predicting the required operating parameters for successful inductive plasma initiation in EAST. The role of wall conditioning on plasma initiation was investigated with the newly developed physical sputtering models of Boron and Lithium. In EAST experiments, it was observed that the discharges after boronisation of the wall are much more vulnerable to plasma burn-through failure than after lithium-coating. The simulation results revealed that despite the similar physical sputtering yield in Boron and Lithium, the radiative energy loss rates for the boron-coated wall are significantly higher than those for the lithium-coated wall, due to the much higher radiative power coefficients of Boron. Parametric scans of initial Boron content in ohmic discharge at the typical prefilled gas pressure in EAST (0.8 mPa) showed that even 1.5% of Boron content in the prefilled gas, possibly remaining after boronisation of the wall, could lead to excessive radiation energy losses and failure of plasma burn-through. For successful plasma burn-through with 1.5% initial boron content, the modelling indicates 10 kW absorption of EC power is required, and it increases with more initial boron e.g. 50 kW for 3% initial boron content.

The sputtering and transport of tungsten (W) impurity in the EAST tokamak have been investigated by the nonlinear magnetohydrodynamic code JOREK. The hybrid kinetic-fluid model in JOREK enables us to study the impacts of the Larmor gyration, sheath acceleration and, W sputtering energy and D+ impinging energy on the W sputtering and transport, which are generally simplified and ignored in fluid transport codes. The simulated W gross erosion flux exhibits a reasonable agreement with the measured data obtained through spectroscopy diagnostics on EAST. By means of the kinetic model in JOREK, it is indicated that the gyration and sheath effects can enhance the W redeposition probability on divertor targets by around three times compared to the fluid treatment. Moreover, the Thompson energy distribution for sputtered W particles has been attempted to survey the influence of the W sputtering energy on the W transport and redeposition, which shows a small discrepancy in the mean free path and redeposition probability of W particles compared to the case with a fixed sputtering energy. The detailed analysis of the W sputtering under the Maxwellian velocity distribution has been conducted, revealing significantly higher W erosion and leakage compared to the monoenergetic case. Eventually, the combined effects of the Larmor gyration, sheath acceleration, W sputtering energy and D+ impinging energy on W transport and redeposition behaviors have been investigated under varying plasma scenarios. It is found that the prompt redeposition of W particles plays a dominant role in the entire W redeposition compared to the long-range redeposition.

In this article, we report a detailed study on the influence of sputter power on physical properties of the NiO films grown by DC magnetron sputtering. Structural studies carried out by Grazing Incidence X-ray diffraction (XRD) reveals the polycrystalline nature of the films with FCC phase. The crystallographic orientation (111) plane followed by (200), (220), and (311) plane were evident from the XRD spectra. The average crystallites sizes were estimated from the spectra, and the values were compared using three different plots such as Scherrer, Williamson–Hall and size–strain plot. The surface morphology was carried out by atomic force microscopy. The deposited samples show semitransparent behavior in the visible region and the estimated band gap increased from 2.70 to 3.34 eV with an increase in sputter power. Furthermore, X-ray photoelectron spectroscopy (XPS) core-level Ni2p spectra were deconvoluted and the observed Ni 2 p 3/2 , Ni 2 p 1 / 2 domain along with their satellite’s peaks were analyzed. Most importantly, XPS quantification data and Raman spectra confirm the presence of both Ni 2 + and Ni 3 + states in the NiO films. The electrical properties carried at room temperature revealed that the resistivity of the film significantly increased and a mobility of ~ 84 cm 2 V - 1 s - 1 was obtained.

This paper presents the experimental results of high-temperature sputtering of nickel targets by the Gas Injection Magnetron Sputtering (GIMS) technique. The GIMS technique is a pulsed magnetron sputtering technique that involves the generation of plasma pulses by injecting small doses of gas into the zone of the magnetron target surface. Using a target with a dedicated construction to limit heat dissipation and the proper use of injection parameters and electrical power density, the temperature of the target during sputtering can be precisely controlled. This feature of the GIMS technique was used in an experiment with sputtering nickel targets of varying thicknesses and temperatures. Plasma emission spectra and current-voltage waveforms were studied to characterize the plasma process. The thickness, structure, phase composition, and crystallite size of the nickel layers produced on silicon substrates were investigated. Our experiment showed that although the most significant increase in growth kinetics was observed for high temperatures, the low sputtering temperature range may be the most interesting from a practical perspective. The excited plasma has the highest energy in the sputtering temperature range, just above the Curie temperature.

Thin films of mixed MoO3 and WO3 were obtained using reactive magnetron sputtering onto ITO-covered glass, and the optimal composition was determined for the best electrochromic (EC) properties. A combinatorial material synthesis approach was applied throughout the deposition experiments, and the samples represented the full composition range of the binary MoO3/WO3 system. The electrochromic characteristics of the mixed oxide films were determined with simultaneous measurement of layer transmittance and applied electric current through the using organic propylene carbonate electrolyte cells in a conventional three-electrode configuration. Coloration efficiency data evaluated from the primary data plotted against the composition displayed a characteristic maximum at around 60% MoO3. Our combinatorial approach allows the localization of the maximum at 5% accuracy.

TiN nano-layered thin films were synthesized using an indigenously built cylindrical magnetron sputtering (CMS) apparatus at varying nitrogen flow rates ranging between 5 and 45 sccm at a constant deposition pressure of 9.5 × 10 −2  mbar. Grazing incidence X-ray diffraction (GIXRD), atomic force microscopy (AFM), laser Raman spectroscopy (LRS), and nano-indentation studies were performed to characterize these as-deposited films. Unlike conventional sputtering, CMS grown films exhibited Stranski–Krastanov (SK) growth with self-assembled nano-hill architecture. The growth of nano-hills is attributed to the shadowing effect of oblique incident flux arising from cylindrical shaped cathode. Additional relaxation based on inverse Hall–Petch formalism brings about indentation induced buckling of nano-hills leading to softening of the TiN films. Higher hill heights at lower nitrogen flow led to increased friction and wear as they are crushed under the applied load generating debris. In contrast, the shorter nano-hills at high nitrogen flow tend to buckle rather than collapse under indenter load resulting in reduced friction. Coefficient of friction value is further influenced by the angle between nano-hill arrays, growth orientation, and indenter sliding directions. Raman spectroscopy data shows the appearance of high wave number anti-symmetric A + O mode for films synthesized at higher argon or nitrogen concentrations.