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Thin films arise in a variety of contexts. They can be between two solid surfaces in the form of a lubricant or with one surface solid and the other free as in water or oil on a road. When the surface tension is a dominant feature of the physics behind the motion, the governing evolution of partial differential equation is nonlinear and of the fourth order in the spatial derivatives. A particular form proposed by King [2001] invites generalization to create a class of equations of higher order. We examine some of the properties of this class in terms of symmetry and singularity and see that there are some open questions which require investigation using different methodologies.

The Zwanzig's procedure (1960) for the description of the system of coupled harmonic oscillators is applied to the chain of interacting oscillations in order to find the adsorption power function, which is then determined by two terms: (i) the classical term proportional to the radio-frequency function squared and (ii) the additional term linear with respect to the radio-frequency magnetic field amplitude. From the physical point of view the first term is usually considered in oscillator effect. The second term found in the present paper via Zwanzig's procedure seems to be induced by fluctuations due to stochastic distributions of the oscillatory precession phases. It reflects well the chaos as described in a fractal approach of the first author (2012, paper joint with M. Nowak-Kȩpczyk and O. Suzuki).

The paper shows the use of Zwanzig's trajectories for spin wave description. The main idea consists in the application of Zwanzig's method to the description of the temporal derivative of magnetization in the direction of rf field in terms of Zwanzig's resolvents found for the magnetization components considered in the harmonic approximation. In particular, the spin waves resonance description can be tested. It reflects well the thermodynamical chaos as described in a fractal approach of the first author (2012, paper joint with Nowak-Kȩpczyk and Suzuki).

Gamma radiation and ozone sensing properties of mixed oxides in the form of thermally evaporated thin films are explored. External effects, such as radiation and ozone cause defects in the materials they interact with, cause changes in the material properties. An Edwards E306A thermal coating system was used for the mixed oxides thin films deposition. Cu electrodes were manufactured on the substrate via thermal evaporation, photoresist was spin-coated over it and was exposed to UV light via acetate containing the desired inter-digitated electrode patterns. After the exposure, the substrate was placed in a developer solution and then rinsed in water and placed in the etching solution to reveal the electrode pattern. The optical properties of the films were explored using CARY 1E UV-Visible Spectrophotometer. The influence of gamma radiation on the electrical properties of the films was traced via the measurements of conductance versus radiation dose, which were recorded in real-time using HP 4277A LCZ impedance analyzer at a frequency of 1 kHz. The fact that the explored thin films were sensitive to both gamma radiation and ozone exposure enables the development of cost-effective real-time monitoring system for personnel protection and environmental monitoring. This novel approach would allow the manufacture of the sensor system with multiple sensor heads during one technological process, whereas various shielding materials or pattern recognition could be employed to differentiate between the effects of ozone and gamma radiation on the mixed oxide thin film sensors.

TiO₂ films were deposited from oxygen/titanium tetraisopropoxide (TTIP) plasmas at low temperature by Helicon-PECVD at floating potential ($V_f)$ or substrate self-bias of $-$50V. The influence of titanium precursor partial pressure on the morphology, nanostructure and optical properties was investigated. Low titanium partial pressure ([TTIP] $<$ 0.013Pa) was applied by controlling the TTIP flow rate which is introduced by its own vapor pressure, whereas higher titanium partial pressure was formed through increasing the flow rate by using a carrier gas (CG). Then the precursor partial pressures [TTIP$+$CG] $=0.027$Pa and 0.093Pa were obtained. At $V_f$, all the films exhibit a columnar structure, but the degree of inhomogeneity is decreased with the precursor partial pressure. Phase transformation from anatase ([TTIP] $<$ 0.013Pa) to amorphous ([TTIP$+$CG] $=0.093$Pa) has been evidenced since the O${}_2^{+}$ ion to neutral flux ratio in the plasma was decreased and more carbon contained in the film. However, in the case of $-$50V, the related growth rate for different precursor partial pressures is slightly ($\sim$ 15%) decreased. The columnar morphology at [TTIP] $<$ 0.013Pa has been changed into a granular structure, but still homogeneous columns are observed for [TTIP$+$CG] $=0.027$Pa and 0.093Pa. Rutile phase has been generated at [TTIP] $<0.013$Pa. Ellipsometry measurements were performed on the films deposited at $-$50V; results show that the precursor addition from low to high levels leads to a decrease in refractive index.

Porous anodic alumina (PAA) thin films, having interconnected pores, were fabricated from Cu-doped aluminum films deposited on $p$-type silicon wafers by anodization. The anodization was done at four different anodizing voltages (60V, 70V, 80V and 90V) in phosphoric acid and two voltages (60V and 70V) in oxalic acid. The aluminum and PAA samples were characterized by SEM and XRD while the pore arrangement, pore density, pore diameter, pore circularity and pore regularity were also analyzed. XRD spectra confirmed the aluminum to be crystalline with the dominant plane being (220), the Cu-rich phase have an average particle size of $15\pm 5$nm uniformly distributed within the Al matrix of 0.4-$\mu$m grain size. The steady-state current density through the anodization increased by 117% and 49% for oxalic and phosphoric acids, respectively, for 10V increase (from 60 to 70 V) in anodization voltage. Similarly, the etching rate increased by 100% for oxalic acid and by 40% for phosphoric acid which are responsible for 47% and 29% decreases in anodization duration, respectively. The highest value of circularity obtained for anodized Al–0.5wt.% Cu formed in oxalic acid at 60V was 0.86, and it was 0.80 for the phosphoric acid at 90V. Anodization of Al–0.5wt.% Cu films allows the formation of circular pores directly on $p$-type silicon wafers which is of importance for future nanofabrication of advanced electronics. The results of anodized Al–0.5wt.% Cu thin film were compared with other anodized systems such as anodized pure Al and Al doped with Si.