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Various properties of HfO2, such as hardness, corrosion, or electrical resistance, depend on the method and the conditions of deposition. In this work, a thorough comparison of scarcely investigated mechanical properties of HfO2 thin films deposited with different conditions of reactive magnetron sputtering process is presented. Four thin films were sputtered in processes that varied in plasma ignition method (continuous or sequential) and target–substrate distance. The structural characteristics of the HfO2 thin films were examined using Raman spectroscopy and X-ray diffraction measurements. Furthermore, the optoelectronic properties were determined based on transmittance and current–voltage characteristics. The mechanical properties of the HfO2 thin films were determined using nanoindentation and scratch test. In turn, the corrosion properties were determined by analyzing the voltametric curves. The transparent HfO2 thin films deposited in the continuous process are characterized by better corrosion resistance than the same layer formed in the sequential process, regardless of the target–substrate distance (8 cm or 12 cm). Furthermore, these samples are also characterized by the highest value of Young's modulus and scratch resistance. The combination of good corrosion and scratch resistance could contribute to the new application of HfO2 as a corrosion protective material. [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 work, a complex examination of vanadium oxide thin films prepared by gas impulse magnetron sputtering with various Ar:O2 gas ratios of 2:1 ÷ 8:1 was conducted. X-ray diffraction revealed the amorphous nature of the prepared thin films, and scanning electron microscopy images showed that the thin films were crack-free and homogenous. Optical properties investigations revealed that a higher oxygen content in the Ar:O2 atmosphere during sputtering caused an increase in transparency. The sample prepared with the highest amount of oxygen in the gas mixture during deposition had 51.1% of the average transmission in the visible wavelength range. A decrease in oxygen caused deterioration in the thin film transparency with the lowest value equal to 21.8%. Electrical measurements showed that the prepared thin films had a semiconducting character with either electron or hole conduction type, depending on the sputtering gas composition. A small amount of oxygen in the gas mixture resulted in the deposition of p-type thin films, whereas an increase in the amount of oxygen caused a change to n-type electrical conduction. Resistivity decreased with increasing Ar:O2 ratio. The gas sensing response toward diluted hydrogen was investigated for all the VxOy thin films, but at low operating temperatures, only the p-type thin films exhibited a visible response. [ABSTRACT FROM AUTHOR]

[Display omitted] • Presents a study of Diamond-like Carbon films with different sp3 content (35–70 %). • The investigated DLC films were deposited by the RF ICP PECVD technique. • Structural, optical, electrical and mechanical properties were investigated. • Points out versatility of DLC films for GaAs/InGaAs-based optoelectronic devices. • Studied DLC films had high plasticity index (0.16) and plastic resistance (0.44). In this paper, a comparison of Diamond-like Carbon (DLC) films with different sp3 fraction content prepared by Radio Frequency Inductively Coupled Plasma Enhanced Chemical Vapour Deposition (RF ICP PECVD) was presented. Structural, surface, optical, and mechanical properties of deposited DLC films were analyzed with the use of a wide range of measurement techniques. The investigated films were deposited on silicon (Si), amorphous silica (SiO 2), and metallic (Ti6Al4V) substrates at room temperature. The deposited DLC films have sp3 fraction content ranging from 35 % to 70 %, uniform, compact and dense microstructure. The investigation indicates that the properties of DLC films required for micro- and optoelectronic applications improve with the sp3 fraction content. The refractive index (n) increased from 1.976 to 2.086, packaging density (PD) from 0.964 to 0.744, electrical resistivity (ρ) from 2.1 ∙ 1010 to 4.4 ∙ 1011 Ωcm, hardness (H) from 16.4 19.1 to GPa and elastic modulus (E) from 109 to 129 GPa. However, the 50 % sp3 DLC thin film exhibited the highest resistance to cracking (H3/E2 = 0.44). The decrease of Urbach energy (E U) from 0.75 to 0.46 eV was observed for the DLC film with the highest sp3 fraction content, while all investigated DLC samples had similar optical bandgap energy (E gopt ≈ 1.3 eV). The research has shown that it is possible to obtain DLC coatings using the RF ICP PECVD technique that has better properties than films deposited by the classic PECVD technique. [ABSTRACT FROM AUTHOR]