01722nas a2200217   4500008004100000022001400041245014700055210006900202300001100271520098900282653000801271653000701279100002301286700001801309700001901327700001901346700002901365700001901394700001901413856007201432       2026                        eng d  a0169-433200aOxidation resistance of organosilicon layered nanostructures synthesized by nonthermal plasma and plasma silica as a source of oxidizing agent0 aOxidation resistance of organosilicon layered nanostructures syn  a1649723 a<p>Plasma polymer (1.2 g cm−3), compact silicon carbide (2.1 g cm−3) and plasma silica (2.2 g cm−3) were synthesized from pure tetravinylsilane vapor or its mixture with argon or oxygen by plasma-enhanced chemical vapor deposition. These materials in the form of nanolayers were combined into layered nanostructures deposited on silicon wafers. XPS depth profiling was used to analyze the chemical depth profiles across the layered nanostructures. The oxidation resistance of highly cross-linked silicon carbide and plasma silica was confirmed after 18 months of storage. However, the plasma polymer with low oxidation resistance must be protected by a 5-nm thick compact silicon carbide barrier to prevent its oxidation. Plasma silica was identified as the source of oxidizing agent for the adjacent plasma polymer in the silica/polymer nanostructure protected by a barrier against the surrounding environment. Oxygen penetrated the polymer by 37 nm in two years.</p>10aAIF10aMF1 aBránecký, Martin1 aJiricek, Petr1 aHoudkova, Jana1 aOlivova, Lucie1 aAboualigaledari, Naghmeh1 aPlichta, Tomas1 aCech, Vladimir  uhttps://www.sciencedirect.com/science/article/pii/S016943322502688102580nas a2200193   4500008004100000022001400041245009200055210006900147300001100216490000800227520198700235653000802222653000702230100001902237700001702256700002202273700001902295856007202314       2023                        eng d  a0257-897200aStable a-CSi:H films with a wide range of modulus of elasticity and low internal stress0 aStable aCSiH films with a wide range of modulus of elasticity an  a1291470 v4593 a<p>Amorphous hydrogenated silicon carbide (a-CSi:H) thin films were deposited by plasma-enhanced chemical vapor deposition using tetravinylsilane as organosilicon precursor. The mechanical properties of the thin films, namely the modulus of elasticity, hardness, and elastic recovery parameter, were determined by nanoindentation, as well as the internal stresses by scanning electron microscopy and optical profilometry. It was found that the modulus of elasticity increased from 10 to 137&nbsp;GPa with increasing power (2–150&nbsp;W) delivered to plasma, while the hardness increased from 1.5 to 14.5&nbsp;GPa. This improvement in mechanical properties with increasing energy delivered to the plasma is related to greater fragmentation of the precursor which led to an increase in the crosslinking of the material network. The compressive internal stresses in the films reached low values of −0.04 to −0.2&nbsp;GPa with increasing power (2–75&nbsp;W) and an acceptable −0.5&nbsp;GPa for 150&nbsp;W. The elastic recovery parameter decreased with increasing power from 0.86 to 0.64, i.e., the thin films behaved more plasticity with increasing power. The modulus of elasticity and hardness were investigated in terms of the aging of the films for a period of 6&nbsp;years when samples were stored under ambient conditions. No significant changes in these properties were observed. However, minor changes were observed in the indentation curves obtained for the 2&nbsp;W and even less for the 10&nbsp;W samples. Small changes were then also observed for the elastic recovery parameter, whose value for these samples partially decreased which may be related to postdeposition oxidation. No changes in internal stress values over time were observed. The wide range of mechanical properties of stable a-CSi:H films with low internal stress increases their application potential and their wide use as materials with tailored properties from polymer-like to tough material.</p>10aAIF10aMF1 aPlichta, Tomas1 aSulc, Vaclav1 aOhlidal, Miloslav1 aCech, Vladimir  uhttps://www.sciencedirect.com/science/article/pii/S025789722201068402627nas a2200181   4500008004100000022001400041245005600055210005600111300001100167490000800178520211100186653000802297653000702305100001902312700002302331700001902354856007202373       2022                        eng d  a0040-609000aSurface topography affects the nanoindentation data0 aSurface topography affects the nanoindentation data  a1391050 v7453 a<p>The near-surface mechanical properties of thin films as well as bulk materials are amongst the key parameters important for their application, and instrumented nanoindentation is a standard technique for determining these mechanical properties. However, it is known that the surface topography of the characterized materials may affect the nanoindentation data when a sharp indenter for small penetration depths (displacements) is used. A thin film of hydrogenated amorphous silicon carbide with a thickness of 1.0&nbsp;μm was deposited on a silicon wafer by plasma-enhanced chemical vapour deposition. The cyclic nanoindentation was used to construct a depth profile of mechanical properties for the flat surface (0.5&nbsp;nm roughness) of the thin film, which made it possible to determine its modulus of elasticity of 83&nbsp;GPa and hardness of 8.6&nbsp;GPa unaffected by the silicon substrate. Grains with a spherical cap geometry with a typical radius of 0.5&nbsp;µm and a&nbsp;height of 60&nbsp;nm are distributed along the flat surface of the film. The grains have the same mechanical properties as the deposited film. Depth profiles of mechanical properties were determined for different types of contact between the Berkovich indenter with a radius of 50&nbsp;nm and the selected grain (grain top, grain foot, two or three grains); i.e. for these measurements the following applied - the radius of the tip curvature was less than grain radii (RBerkovich &lt; Rgrain). Residual imprints after nanoindentation measurements were carefully observed by atomic force microscopy and scanning electron microscopy. The near-surface mechanical properties were significantly affected by the surface topography, and the determined modulus of elasticity and hardness were crucially under- or overestimated in the range of 50% to 100% compared to the real values. The nature of these deviations was discussed. The solution is to use cyclic nanoindentation performed on the flat surfaces or on the top of grains, followed by extrapolation of the depth profiles to the zero-contact depth (film surface).</p>10aAIF10aMF1 aPlichta, Tomas1 aZahradnicek, Radim1 aCech, Vladimir  uhttps://www.sciencedirect.com/science/article/pii/S0040609022000268