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Thin films of copper oxide (CuxO), titanium oxide (TiOx), and several mixtures of copper and titanium oxides ((CuTi)Ox) were deposited using magnetron sputtering. X-ray diffraction analysis of the as-deposited TiOx thin film revealed the presence of TiO crystallites, while in the case of (CuTi)Ox with the lowest amount of copper, metallic Cu crystallites were found. In the case of (Cu0.77Ti0.23)Ox and CuxO thin films, characteristic peaks for metallic copper and copper oxides were observed in their diffractograms. It was found that post-process annealing at 473 K considerably affects the microstructure of (CuTi)Ox thin films. After annealing, anatase phase was observed in (Cu0.23Ti0.77)Ox and (Cu0.41Ti0.59)Ox thin films. In turn, the (Cu0.77Ti0.23)Ox and CuxO films were formed only in the copper oxide phase. The (Cu0.77Ti0.23)Ox film annealed at 473 K showed the best opto-electronic performance, as it had the highest transmission and the lowest resistivity. However, the greatest advantage of this thin film was the p-type semiconducting behavior, which was the strongest of all of the thin films in this work, as indicated by the measurement of the Seebeck coefficient. All deposited thin films were sensitive to hydrogen exposure, while the best sensor response of 10.9 was observed for the (Cu0.77Ti0.23) Ox thin film annealed at 473 K. [ABSTRACT FROM AUTHOR]

This paper reports results of investigations on selected properties of vanadium oxide thin films deposited using gas impulse magnetron sputtering and annealed at temperatures in the range of 423 K to 673 K. Post-process annealing was shown to allow phase transition of as-deposited films from amorphous to nanocrystalline V2O5 with crystallite sizes in the range of 23 to 27 nm. Simultaneously, annealing resulted in an increase in surface roughness and grain size. Moreover, a decrease in transparency was observed in the visible wavelength range of approximately 50% to 30%, while the resistivity of formed vanadium pentoxide thin films was almost unchanged and was in the order of 102 Ω·cm. Simultaneously, the best optoelectronic performance, testified by evaluated figure of merit parameter, indicated the as-deposited amorphous films. Performed Seebeck coefficient measurements indicated the electron type of electrical conduction of each prepared thin film. Furthermore, gas sensing properties towards diluted hydrogen were investigated for annealed V2O5 thin films, and it was found that the highest senor response was obtained for a thin film annealed at 673 K and measured at operating temperature of 623 K. [ABSTRACT FROM AUTHOR]

The paper presents the results of an investigation of the influence of technological parameters on the microstructure, optical, electrical and nanomechanical properties of zinc oxide coatings prepared using the pulsed reactive magnetron sputtering method. Three sets of ZnOx thin films were deposited in metallic, shallow dielectric and deep dielectric sputtering modes. Structural investigations showed that thin films deposited in the metallic mode were nanocrystalline with mixed hexagonal phases of metallic zinc and zinc oxide with crystallite size of 9.1 and 6.0 nm, respectively. On the contrary, the coatings deposited in both dielectric modes had a nanocrystalline ZnO structure with an average crystallite size smaller than 10 nm. Moreover, coatings deposited in the dielectric modes had an average transmission of 84% in the visible wavelength range, while thin films deposited in the metallic mode were opaque. Measurements of electrical properties revealed that the resistivity of as-deposited thin films was in the range of 10−4 Ωcm to 108 Ωcm. Coatings deposited in the metallic mode had the lowest hardness of 2.2 GPa and the worst scratch resistance among all sputtered coatings, whereas the best mechanical properties were obtained for the film sputtered in the deep dielectric mode. The obtained hardness of 11.5 GPa is one of the highest reported to date in the literature for undoped ZnO. [ABSTRACT FROM AUTHOR]

In this paper, comparative studies on the structural, surface, optical, mechanical and corrosion properties of titanium dioxide (TiO2) thin films deposited by continuous and sequential magnetron sputtering processes were presented. In case of continuous process, magnetron was continuously supplied with voltage for 90 min. In turn, in sequential process, the voltage was supplied for 1 s alternately with 1 s break, therefore, the total time of the process was extended to 180 min. The TiO2 thin films were crack free, exhibited good adherence to the substrate and the surface morphology was homogeneous. Structural analysis showed that there were no major differences in the microstructure between coatings deposited in continuous and sequential processes. Both films exhibited nanocrystalline anatase structure with crystallite sizes of ca. 21 nm. Deposited coatings had high transparency in the visible wavelength range. Significant differences were observed in porosity (lower for sequential process), scratch resistance (better for sequential process), mechanical performance, i.e. hardness:elastic modulus ratio (higher for sequential process) and corrosion resistance (better for sequential process). [ABSTRACT FROM AUTHOR]

Titanium dioxide thin films were prepared using two types of magnetron sputtering processes: conventional and with modulated plasma. The films were deposited on SiO2 and Si substrates. X-ray diffraction measurements of prepared coatings revealed that the films prepared using both methods were nanocrystalline. However, the coatings deposited using conventional magnetron sputtering had anatase structure, while application of sputtering with modulated plasma made possible to obtain films with rutile phase. Investigations performed with the aid of scanning electron microscope showed significant difference in the surface morphology as well as the microstructure at the thin film cross-sections. The mechanical properties of the obtained coatings were determined on the basis of nanoindentation and abrasion resistance tests. The hardness was much higher for the films with the rutile structure, while the scratch resistance was similar in both cases. Optical properties were evaluated on the basis of transmittance measurements and showed that both coatings were well transparent in a visible wavelength range. Refractive index and extinction coefficient were higher for TiO2 with rutile structure. [ABSTRACT FROM AUTHOR]

In this work, selected properties of metallic and oxide thin films based on titanium and cobalt were described. Thin-film coatings were prepared using the magnetron sputtering method. The deposition was carried out from sintered targets with different Co-content (2 at.%, 12 at.% and 50 at.%). The relation between the Ti–Co target composition and the Co-content in the metallic and oxide films was examined. There was 15–20% more cobalt in the films than in the target. Moreover, the deposition rate under neutral conditions (in Ar plasma) was even 10-times higher compared to oxidizing Ar:O2 (70:30) plasma. A comprehensive analysis of the structural properties (performed with GIXRD and SEM) revealed the amorphous nature of (Ti,Co)Ox coatings, regardless of the cobalt content in the coating. The fine-grained, homogenous microstructure was observed, where cracks and voids were identified only for films with high Co-content. Optical studies have shown that these films were well transparent (60% ÷ 80%), and the amount of cobalt in the target from which they were sputtered had a significant impact on the decrease in the transparency level, the slight shift of the absorption edge position (from 279 nm to 289 nm) as well as the decrease in their optical band gap energy (from 3.13 eV to 1.71 eV). Electrical studies have shown that in (Ti,Co)Ox thin films, a unipolar memristive-like effect can be observed. The occurrence of such effects has not been reported so far in the case of TiO2 coatings with the addition of Co. [ABSTRACT FROM AUTHOR]