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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.

The half-metallic Heusler compound Co₂MnSi is a very attractive material for spintronic devices because it exhibits very high tunnelling magnetoresistance ratios. This work reports on a spectroscopic investigation of thin Co₂MnSi films as they are used as electrodes in magnetic tunnel junctions. The investigated films exhibit a remanent in-plane magnetization with a magnetic moment of about 5 μ_B when saturated, as expected. The low coercive field of only 4 mT indicates soft magnetic behavior. Magnetic dichroism in emission and absorption was measured at the Co and Mn 2p core levels. The photoelectron spectra were excited by circularly polarized hard X-rays with an energy of 6 keV and taken from the remanently magnetized film. The soft X-ray absorption spectra were taken in an induction field of 4 T. Both methods yielded large dichroism effects. An analysis reveals the localized character of the electrons and magnetic moments attributed to the Mn atoms, whereas the electrons related to the Co atoms contribute an itinerant part to the total magnetic moment.

The porphyrin macrocycle is one of the most frequently investigated functional molecular entities and can be incorporated into advanced functional nanomaterials upon formation of organized nanostructures. Thus, study of the science and technology of porphyrin assemblies has attracted many organic, biological and supramolecular chemists. A wide variety of nanostructures can be obtained by supramolecular self-assembly because the porphyrin moiety is amenable to chemical modifications through thoughtful synthetic design and moderate preparative effort. Some recent developments in porphyrin assembly, obtained through various supramolecular approaches, are briefly summarized. Topics described in this review are classified into four categories: (i) non-specific assemblies; (ii) specific assemblies; (iii) assemblies in organized films; (iv) molecular-level arrangement. We present examples in the order of structural precision of assemblies.

In this study, nc-ZnO films deposited in a Pulsed Laser Deposition (PLD) system at various temperatures were used to fabricate high performance transistors. As determined by Transmission Electron Microscope (TEM) images, nc-ZnO films deposited at a temperature range of 25°C to 400°C were made of closely packed nanocolums showing strong orientation. The influences of film growth temperature and post growth annealing on device performance were investigated. Various gate dielectric materials, including SiO₂, Al₂O₃, and HfO₂ were shown to be suitable for high performance device applications. Bottom-gate FETs fabricated on high resistivity (>2000 ohm-cm) Si substrates demonstrated record DC and high speed performance of any thin film transistors. Drain current on/off ratios better than 10¹² and sub-threshold voltage swing values of less than 100mV/decade could be obtained. Devices with 2μm gate lengths produced exceptionally high current densities of >750mA/mm. Shorter gate length devices (L_G=1.2μm) had current and power gain cut-off frequencies, f_T and f_max, of 2.9GHz and 10GHz, respectively.