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In this study, the deposition and characteristics of Si- and Ti-series multilayer coatings with respective glass/Si 3 N 4 /NiCr/Ag/NiCr/Si 3 N 4 and glass/TiO 2 /ZnSnO 3 /ZnO/Ag/NiCrO x /ZnSnO 3 /Si 3 N 4 structures were investigated. Experimental analyses were performed, and the optical performance and thermal stability of the coatings were assessed. The as-deposited Si- and the Ti-series samples exhibited optimal shading coefficient of 0.49 and 0.57, respectively. Thermal annealing in air was performed to analyze the thermal stability and oxidation resistance of the samples. The Si- and Ti-series samples prevented the failure of low-emissivity properties at 700 and 600 °C, respectively. In addition to high transparency, the Si-series samples exhibited improved low-emissivity properties, reduced light pollution, and superior thermal stability compared to the Ti-series samples. The use of Si 3 N 4 and NiCr layers effectively prevented the oxidation and cracking of the Ag layer upon heat treatment. This study presents the characteristics of Si- and Ti-series samples for energy-saving building applications. [ABSTRACT FROM AUTHOR]

The dependence of the structure of (TiZrHf)N coatings deposited by reactive magnetron sputtering on different working pressures and their mechanical and electro-optical properties were investigated. The increased working pressure contributed to the decreased oxygen contamination. With increased working pressure, the compressive stress was transitioned to tensile one. Compressively stressed coatings consisted of tightly packed columns with a smooth surface. The tensile stressed coatings presented void network structure surrounding the columnar grains with a rough surface. Moreover, the grain size initially increased and subsequently decreased. Accordingly, the (TiZrHf)N coatings deposited at high working pressure were characterized with poor hardness, low electrical conductivity, and low light reflectivity due to the porous structure and high oxygen contamination. In addition, the coating color changed from bright gold to dark gray. In this study, the working pressure was proven a sensitive deposition parameter in controlling the microstructure, mechanical, and electro-optical properties of the coating. The wide structural variation in the (TiZrHf)N coatings allowed a diverse physical performance suitable for a broad range of applications. [ABSTRACT FROM AUTHOR]

Within the frame of this work, reactive magnetron-sputtered (TiZrHf)N coatings were deposited on Si substrates. The depositions were carried out from a pure TiZrHf target with varying N 2 -to-total (N 2 +Ar) flow ratios, R N . The TiZrHf alloy and its nitride coatings exhibited body-centered cubic and face-centered cubic crystal structures, respectively. The increase in R N contributed to the decrease in O 2 contamination. For nitrides, with increasing R N , the grain size decreased to a nano-sized level. Consequently, the microstructure of the nitride coatings was converted from a large columnar structure with rough surface to a fine columnar structure with a smooth surface. Moreover, the compressive stress and the corresponding lattice parameter increased initially and then decreased. The golden-like (TiZrHf)N coatings deposited at R N =20% exhibited the highest hardness of 40.7 GPa, which attained the superhard grade. Meanwhile, low electrical resistivity of 129.2 μΩ-cm and high reflectivity at 0.62 eV of 84.0% were obtained. The electro-optical behavior of (TiZrHf)N coatings was demonstrated further by spectroscopic ellipsometry on the basis of their dielectric function and energy loss function. The gold-colored (TiZrHf)N coating with excellent physical properties has a wide range of diverse potential industrial applications. [ABSTRACT FROM AUTHOR]

We investigated the effects of sputtering power on the microstructure of direct-current magnetron sputter-deposited TiVCr films on silicon wafer grown at room temperature. When the sputtering power was 100 W, composite structure with amorphous and body-centered cubic (BCC) crystal phases can be observed. When sputtering power was increased to 200 W, the composite structure was almost transformed into crystal columnar structure. Apart from interface region, the amorphous zone was composed of bundles of fine fibrous structure, whereas the BCC crystal zone contained V-shaped columnar structures without significant element segregation. Results indicated that the high sputtering power favored the formation of crystal films and the decrease of intracolumnar voids. However, a significant crack occurred, thereby widening intercolumnar voids. The film deposited at high sputtering power demonstrates slight improvement of mechanical properties. [ABSTRACT FROM AUTHOR]

Various (AlCrMoTaTi)-Si x -N coatings were prepared on Si substrates through a reactive magnetron sputtering system to methodically investigate the effects of Si contents and free Si on oxidation behavior. The as-deposited Si-containing coating presented a relatively dense and compact structure compared with the Si-free coating. An oxide layer was formed on the coating surface and continued to thicken when the coatings were exposed to ambient air at elevated temperatures. At 1073 K, a two-layer structure, which consists of an amorphous Al 2 O 3 layer with traces of other target elements followed by a rutile TiO 2 + oxide of the target element mixed zone, was developed in the oxide layer. Oxidation resistance was gradually enhanced with the continued increase in Si concentration in the coatings. At 1173 K, the coatings with Si content of as low as 7.51 at.% exhibited a single order of magnitude lower oxidation rate than that of the Si-free coating. Nanohardness measurement of the coatings further confirmed the oxidation behavior. The significantly enhanced oxidation resistance may be attributed to the presence of Al and Si in the coatings. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effects of discharge power on the composition and the microstructural, mechanical, and electro-optical properties of (TiZrHf)N coatings. The coatings were deposited on Si substrates via reactive magnetron sputtering. The coatings were deposited at varying discharge powers (50–300 W). At low discharge powers, amorphous structures were produced during the initial sputtering period. High (2 0 0)-axis orientation structures were formed when sputtering time was increased. The upper part of the coatings was composed of open columnar structures with extended voids along the column boundaries. Increasing the discharge power decreased the thickness of the amorphous layer. Consequently, the microstructures became dense and compact; however, the grain size did not change significantly. Meanwhile, an enhanced compressive stress was observed, followed by an increase in the texture coefficients of the (1 1 1) plane and lattice parameters. The physical properties of the coatings were improved by increasing the discharge power. The coating hardness was increased to approximately 32.1 GPa. In addition, the electrical resistivity was decreased to approximately 134 μΩ cm, and the light reflectivity in the infrared region (700–2400 nm) was increased to 75%. [ABSTRACT FROM AUTHOR]

Si-doped (AlCrMoTaTi)N coatings were deposited onto an Si substrate by radio-frequency magnetron sputtering of an AlCrMoTaTi alloy target under direct current bias in an N 2 /Ar atmosphere. The crystal, microstructural, mechanical, and electrical properties at different Si-target powers were investigated. As the Si content reached 7.51 at.%, the simple NaCl-type face-centered cubic structure of nitride was retained. Significant lattice decline and grain growth were observed in the nitride coatings. The microstructure of coatings transformed from loose columns with rough-faceted surface into dense ones with smooth-domed surface. The solubility of approximately 7.51 at.% Si content was demonstrated. Si incorporation significantly improved the mechanical properties of the coatings, but degraded their electrical properties. The hardness of the coatings increased from 20.7 GPa to 35.5 GPa, and the electrical resistivity increased from 793 μΩ cm to 3872 μΩ cm. [ABSTRACT FROM AUTHOR]

Abstract: (TiVCrZrHf)N coatings prepared using quinary metallic elements were deposited by reactive magnetron sputtering. The effects of post vacuum annealing on the structure and properties of the coatings were investigated using different analytical instruments. The (TiVCrZrHf)N coatings showed continuous changes in the microstructure as the coating thickness increased. A 270nm-thick amorphous layer was initially formed, followed by a columnar structure with a face-centered cubic phase. The crystal structure and microstructure of the coatings remained unchanged after annealing at 1073K. The amorphous layer appeared at an annealing temperature of 1173K. Furthermore, a Cr–Si solid state phase was observed near the substrate. The coatings nearly independent of the postannealing temperature exhibited a hardness of 31GPa and an electrical resistivity of 150μΩcm. In addition, a 15nm-thick (TiVCrZrHf)N coating was used as a potential diffusion barrier for metallization. The (TiVCrZrHf)N barrier layer failed after annealing at 1173K. Severe interdiffusion of Si and Cu through the layers was observed, and a large amount of Cu silicides was formed. [Copyright &y& Elsevier]

Highlights: [•] The R N influences the structure and properties of (AlCrMoTaTi)N coatings. [•] The alloy coating has a composite structure with amorphous and bcc crystal phases. [•] The nitride coating displays V-shaped columnar structure with fcc crystal phase. [•] Increasing R N to 30% caused the hardness to reach maximum values of 30.6GPa. [•] Electrical resistivity increased to 8212μΩcm when R N increased to 50%. [ABSTRACT FROM AUTHOR]

(TiVCrZrHf)N coatings were deposited on Si substrates by reactive magnetron sputtering system. Their oxidation behaviors and structure were studied after static oxidation tests in air at different temperatures. The evolution of the chemical composition, microstructure, nanohardness, and electrical resistivity of these coatings after annealing at different temperatures in air was systematically analyzed. The as-deposited coating showed continued variation in structure from amorphous to columnar with the face-centered cubic crystal phase, but had no significant change in structure with increased annealing temperature to 300°C. The hardness of the coating was stable at a high value of 31.24GPa up to an annealing temperature of 300°C. However, a thin oxide overlayer was observed at 400°C, which increased in thickness at 500°C and thus drastically decreasing the hardness to 11.85GPa. Above 600°C, the coating was almost fully oxidized and became quite porous and loose. Accordingly, a very low hardness of only 2.3GPa was obtained. The electrical resistivity of the coatings followed the same trend as the hardness. The electrical resistivity of the as-deposited coating was about 144μΩ-cm, followed by an apparent increase to 100Ω-cm due to the formation of oxide phases. [ABSTRACT FROM AUTHOR]

Abstract: Ti–V–Cr–Al–N films were prepared by dc magnetron co-sputtering by utilizing TiVCr and Al targets. By using glancing incidence X-ray diffraction, a single NaCl solid solution phase with (200) preferred orientation for the Al-doped films was revealed, as opposed to the undoped films that possessed predominantly (111) preferred orientation. This indicates that Al addition can lead to the enhancement of adatom mobility and consequently, to a thermodynamically favorable (200) orientation. This also leads to grain growth and increased surface roughness. However, based on results from transmission electron microscopy, the microstructure morphology seemed independent of the Al concentration, implying that adatom mobility is not sufficient for the barriers present at the grain boundaries. Accordingly, hardness was enhanced by the increase in Al concentration. [Copyright &y& Elsevier]

Abstract: In this study, we investigated the microstructure of (TiVCrZrHf)N multi-element coating deposited on Si(100) substrate by magnetron sputtering system. Interestingly, the film showed an unusual structure evolution. A continuous and amorphous initial (TiVCrZrHf)N layer formed on the substrate. As film thickness increased, randomly oriented small (TiVCrZrHf)N grains formed, followed by the development of columnar grains with FCC crystal phase. In contrast to previous studies, the nitride coatings grew on substrates with a 270-nm amorphous interlayer. Under appropriate parameters, the occurrence of the unusual microstructure could be attributed to the sluggish diffusion of the multi-principal components. The maximum hardness of 33.5GPa was obtained when coating was deposited under substrate bias of −100V and at substrate temperatures of 723K. [Copyright &y& Elsevier]

Abstract: (TiVCrZrHf)N coatings were deposited via reactive radio-frequency (RF) magnetron sputtering at different substrate biases (0 to 200V). The chemical composition, microstructure, and mechanical properties of the coatings were investigated. As the substrate bias increased, the preferred orientation of the (TiVCrZrHf)N coatings changed from (111) to (200). Reduced grain size and surface roughness were also observed. The microstructure obviously changed, from a V-shaped columnar structure with clearly faceted surface features to a highly dense structure with a very smooth surface. Moreover, a continuous variation in the microstructure, from randomly oriented nanograins to columns with a face-centered cubic (FCC) phase, was evident. The hardness of the coatings deposited at 100V or higher was around 32–33GPa. The structural evolution and strengthening mechanism of the coatings were also discussed. [Copyright &y& Elsevier]

Abstract: In this study, TiVCr alloy coatings were deposited on Si substrates by magnetron sputtering system at different working pressures (0.33–1Pa). The TiVCr coatings have a composite structure with amorphous and body-centered cubic (bcc) crystal phases comprised of bundles of fine fibrous structures and V-shaped columnar structures, respectively. Compared with the amorphous zone, the crystalline zone has a denser and more compact structure. The coating microstructure became more porous as working pressure increased. Consequently, the crystal zones of the deposited coatings at 0.33Pa obtained higher hardness (11.6GPa) while the deposited coatings at 1Pa achieved lower hardness (4.5GPa). [ABSTRACT FROM AUTHOR]

Abstract: The (TiVCr)N coatings were deposited on Si substrate via rf magnetron sputtering of a TiVCr alloy target under dc bias in a N2/Ar atmosphere. The deposition rate of the coatings gradually decreased with increasing N2-to-total (N2 +Ar) flow ratio, R N. The TiVCr alloy and its nitride coatings exhibited a body-centered cubic (BCC) and a face-centered cubic (FCC) crystal structure, respectively. The preferred orientation of the (TiVCr)N coatings changed from (111) to (200) with increasing R N. In addition, the microstructure of the nitride coatings was also converted from a columnar structure with void boundaries and rough-faceted surface to a very dense structure with a smooth-domed surface. The grain size of the (TiVCr)N coatings decreased as the R N was increased. Accordingly, the hardness of the (TiVCr)N coatings was enhanced from 4.06 to 18.74GPa as the R N was increased. [ABSTRACT FROM AUTHOR]

Abstract: This study reports the influence of growth conditions on the characteristics of (TiVCrZrY)N coatings prepared by reactive magnetron sputtering at various N2-to-total (N2 +Ar) flow ratio, which is RN. The crystal structures, microstructure, and mechanical properties for different RN were characterized by electron spectroscopy for chemical analysis, X-ray diffraction, atomic force microscopy, field-emission-scanning electron microscopy, transmission electron microscopy, and nanoindentation. The results indicate that the TiVCrZrY alloy and nitride coatings have hexagonal close-packed (hcp)-type and sodium chloride (NaCl)-type solid–solution structures, respectively. The voids in the coatings are eliminated and the growth of the columnar crystal structures is inhibited along with an increasing RN. As a consequence, highly packed equiaxed amorphous structures with smooth surfaces are formed. The coatings accordingly achieved a pronounce hardness of 17.5GPa when RN =100%. [ABSTRACT FROM AUTHOR]

Abstract: The present paper reports the influence of growth conditions on the characteristics of (TiVCrZrHf)N films prepared by rf reactive magnetron sputtering at various substrate temperatures. The nitrogen content is observed to decrease with increasing substrate temperature. The X-ray diffraction results indicate that all (TiVCrZrHf)N films are simple face centered cubic (FCC) structures. Initially, there is an obvious decrease followed by an increase in grain size with the increase in substrate temperature. The lower part of the microstructure has an amorphous structure. A nano grain structure (size ∼1nm) with a random orientation is also observed above the amorphous structure. The fully dense columnar structure with an fcc crystal phase then starts to develop. Extreme hardness of around 48GPa is obtained in the present alloy design. [Copyright &y& Elsevier]