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Nickel films of 40 nm thickness were obtained by means of magnetron sputtering on a single-crystalline silicon substrate. The films were subjected to rapid thermal treatment (RTT) for 7 s until the temperature increased from 200 to 550 °C. By means of the X-ray diffraction method, the structural-phase composition of nickel films before and after RTT was explored. The atomic force microscopy method due to direct contact with the surface under study, made it possible to accurately define the microstructure, roughness, specific surface energy and grain size of the nickel films before and after RTT, as well as to establish the relationship of these parameters with the phase composition and electrical properties of the films. Surface specific resistance was measured using the four-probe method. Based on XRD results, formation of Ni2Si and NiSi phases in the film was ascertained after RTT at 300 °C. At RTT 350–550 °C, only the NiSi phase was formed in the film. The microstructure and grain size significantly depend on the phase composition of the films. A correlation has been established between specific surface energy and resistivity with the average grain size after RTT at 350–550 °C, which is associated with the formation and constant restructuring of the crystal structure of the NiSi phase. [ABSTRACT FROM AUTHOR]

Utilizing reactive DC magnetron sputtering method, TiN coatings were deposited on the silicon substrates at different nitrogen flows and powers. A study of the X-ray phase composition of the coatings was carried out. The stoichiometric composition of the coatings was determined using energy dispersive x-ray spectroscopy. The structure of the surface, cross-section, and thickness of the coatings were determined using scanning electron (SEM) and atomic force microscopy (AFM). A significant change in the surface structure of TiN coatings was established with changes in deposition power and nitrogen flow. SEM images of cross-sections of all coated samples showed that the formation of coatings occurs in the form of a columnar structure with a perpendicular orientation relative to the silicon substrate. The mechanical properties (elastic modulus E and microhardness H) of TiN coatings of the first group demonstrate a maximum at a nitrogen flow of 3 sccm and are 184 ± 11 GPa and 15.7 ± 1.3 GPa, respectively. In the second group, the values of E and H increase due to a decrease in the size of the structural elements of the coating (grains and crystallites). In the third group, E and H decrease. Microtribological tests were carried out in 4 stages: at a constant load, multi-cycle for 10 and 100 cycles, and with increasing load. The coefficient of friction (CoF) and specific volumetric wear ω depend on the roughness, topology, and mechanical properties of the resulting coatings. Fracture toughness was determined using nanoscratch and depends on the mechanical properties of TiN coatings. Within each group, coatings with the best mechanical and microtribological properties were described: in the first group—TiN coating at 3 sccm (with (29.6 ± 0.1) at.% N), in the second group—TiN coating at 2 sccm (with (40.8 ± 0.2) at.% N), and in the third group—TiN coating at 1 sccm (c (37.3 ± 0.2) at.% N). [ABSTRACT FROM AUTHOR]

The present paper addresses the problem of identification of microstructural, nanomechanical, and tribological properties of thin films of tantalum (Ta) and its compounds deposited on stainless steel substrates by direct current magnetron sputtering. The compositions of the obtained nanostructured films were determined by energy dispersive spectroscopy. Surface morphology was investigated using atomic force microscopy (AFM). The coatings were found to be homogeneous and have low roughness values (<10 nm). The values of microhardness and elastic modulus were obtained by means of nanoindentation. Elastic modulus values for all the coatings remained unchanged with different atomic percentage of tantalum in the films. The values of microhardness of the tantalum films were increased after incorporation of the oxygen and nitrogen atoms into the crystal lattice of the coatings. The coefficient of friction, CoF, was determined by the AFM method in the "sliding" and "plowing" modes. Deposition of the coatings on the substrates led to a decrease of CoF for the coating-substrate system compared to the substrates; thus, the final product utilizing such a coating will presumably have a longer service life. The tantalum nitride films were characterized by the smallest values of CoF and specific volumetric wear. [ABSTRACT FROM AUTHOR]

• ZrN coatings were grown on the polished steel substrates at the different N flow rate. • Nanocrystalline microstructure of the surface are explored by AFM analysis. • The main texture of ZrN phase changes from (111) to (200) with the increase of N. • E and H were analyzed by nanoindentation. ZrN coatings with the thickness of about 3 μm were deposited on hardened steel substrates by reactive magnetron sputtering at the constant magnetron power of 700 W and at the substrate bias voltage about − 10 V with different nitrogen flow rate from 3 to 6 sccm. The surface investigations were carried out using scanning electron microscopy, atomic-force microscopy, nanoindentation and glancing-angle X-ray diffraction. It was found that the texture of ZrN phase, the mechanical properties and the size of grains in the polycrystalline ZrN coatings can be controlled using different nitrogen flows. [ABSTRACT FROM AUTHOR]

Thin films of NiCr–C were deposited by pulse magnetron sputtering of the NiCr20 alloy cathode in an atmosphere containing a mixture of argon and acetylene. Their structure, chemical composition, and magnetic properties were studied using X-ray diffraction, X-ray photoelectron spectroscopy, high-resolution transmission electron microscopy, atomic and magnetic force microscopy, and superconducting quantum interference magnetometry methods. Film amorphisation observed upon increasing carbon content was followed by amorphous carbon segregation. As a result of the self-assembly processes during the coating growth, nanostructures were obtained consisting of metallic columns surrounded in carbon sheaths, with axes parallel to the growth direction. The resulting films exhibited weak ferromagnetism in a direction parallel to the axis of the nanocolumns, while the system's response was superparamagnetic for the direction of magnetisation perpendicular to the nanocolumns. • NiCr–C coatings were deposited by reactive magnetron sputtering of the NiCr20 alloy. • Coatings are crystalline, amorphous or nano-structured depending on the carbon content. • The nano-structured coatings consist of metallic nanocolumns in carbon sheaths. • Foils containing 43 % at. C are ferro- or superparamagnetic depending on the direction. • The spin blocking temperature was determined to be about 115 K. [ABSTRACT FROM AUTHOR]