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Here we report the influence of Sb doping on the structural and optical properties of Zn 1− x Sb x Se (0 ⩽ x ⩾ 0.15) thin films prepared by thermal evaporation technique on glass substrate. Various characterization techniques such as X-ray diffraction (XRD), EDS, Raman spectroscopy and spectroscopic ellipsometer are employed to assess the structural and optical properties of the deposited films. XRD analysis reveals the formation of polycrystalline cubic structure having preferred growth orientation along (1 1 1) plane without any evidence of secondary phases. Crystallographic parameters like grain size, micro strain, dislocation density, number of crystallites per unit area and texture coefficient point out the structural modification in ZnSe films with Sb inclusion. Raman analysis shows the existence of three 1LO, 2LO and 3LO phonon modes at 251, 511 and 745 cm −1 in pure ZnSe while 3LO mode disappears by the incorporation of Sb atoms in ZnSe matrix. Increase in FWHM of Raman peaks with Sb concentration also indicates the change in crystalline quality of ZnSe films which is in accordance with our XRD results. Spectroscopic ellipsometry results demonstrate a decreasing trend for the optical band gap energy (from 2.61 eV to 1.81 eV) with increasing Sb content. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents the design of quarter-wave retarders for the dense wave division multiplexing using parallel mirrors coated with a single layer. The output light from the device is parallel to the input light and displaced by a distance d. The quarter-wave retarder''s total reflection is in the range of 83%. Error analysis on the design is also presented. Error analysis shows how changes on the angle of incident light and the thin film thicknesses affect the design of the retarders. [Copyright &y& Elsevier]

Abstract: ZnS thin films with a c-axis preferred orientation have been prepared by sulfurizing the RF reactive sputter deposited ZnO thin films at 500°C in sulfur vapor. These thin films have been characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), UV–visible transmission spectra and Auger electron spectroscopy (AES). It is found that the degree of c-axis orientations of ZnO and ZnS thin films increases with enhancing RF power. Also, the sulfurized thin films have markedly greater grains than the as-deposited films, mainly due to recrystallization of ZnS in sulfur vapor. The grain size for the ZnS films increases from ∼200 to ∼500nm with enhancing RF power from 80 to 120W. A reason for this is that in the case of the greater RF power, high compactness of the films will be very beneficial to the grain growth. Additionally, the excess sulfur can be absorbed on the grain surface of the ZnS film produced by 22h sulfidation. This will cause the great broadening of absorption edge in the optical transmittance. [Copyright &y& Elsevier]

Abstract: The effect of the ratio of fluctuation field (H f) to coercivity (H c) on the temperature coefficient of coercivity [α(H c)] was investigated for Co55Cr15.5Pt28B1.5/Co63Cr37/Cr, Co69Cr19Pt9Ta3/Cr, and Co86Cr10Ta4/Cr thin films (longitudinal recording media) with very small average grain volume (V phy). α(H c) increases markedly with increase in temperature between near 250 and 350K for Co55Cr15.5Pt28B1.5/Co63Cr37/Cr thin films. α(H c) is approximately proportional to the ratio H f/H c for all thin films, as in the case of advanced data backup tapes prepared from ultrafine particles. α(H c) and the ratio H f/H c increase as V phy decreases. Smaller H f/H c values are necessary for small α(H c) values, which is very important for the thermal stability of high-density recording media with very small V phy. [Copyright &y& Elsevier]

Abstract: Single-phase perovskite structure Pb1− x Ba x TiO3 thin films (x=0.30, 0.50 and 0.70) were deposited on Pt/Ti/SiO2/Si substrates by the spin-coating technique. The dielectric study reveals that the thin films undergo a diffuse type ferroelectric phase transition, which shows a broad peak. An increase of the diffusivity degree with the increasing Barium contents was observed, and it was associated to a grain decrease in the studied composition range. The temperature dependence of the phonon frequencies was used to characterize the phase transition temperatures. Raman modes persist above tetragonal to cubic phase transition temperature, although all optical modes should be Raman inactive. The origin of these modes was interpreted in terms of breakdown of the local cubic symmetry by chemical disorder. The absence of a well-defined transition temperature and the presence of broad bands in some interval temperature above FE–PE phase transition temperature suggested a diffuse type phase transition. This result corroborates the dielectric constant versus temperature data, which showed a broad ferroelectric phase transition in these thin films. The leakage current density of the PBT thin films was studied at different temperatures and the data follow the Schottky emission model. Through this analysis the Schottky barrier height values 0.75, 0.53 and 0.34eV were obtained to the PBT70, PBT50 and PBT30 thin films, respectively. [Copyright &y& Elsevier]

Abstract: Titanium phthalocyanine dichloride (TiPcCl2) thin films are prepared on glass substrates by vacuum-sublimation technique. The optical constants of thin films are obtained by means of thin film spectrophotometry. Planar structures for the study of electrical properties are fabricated with TiPcCl2 as active layer and silver as the contact electrodes. The effects of post-deposition annealing on the optical band gap have been studied. The optical transition is found to be direct allowed in nature. The invariance in the optical band gap shows the thermal stability of the material. The activation energies are determined using the Arrhenius plots between electrical conductivity and inverse temperature. The variation in activation energy with post-deposition annealing is investigated. The unit cell dimensions of TiPcCl2 thin films are also determined by indexing the powder diffraction data. The variations of the surface morphology and grain size with annealing have also been studied. [Copyright &y& Elsevier]

Abstract: Thin chalcogenide films of Ge1− x Se2Pb x (x=0, 0.2, 0.4, 0.6 and 0.8) have been prepared by the thermal evaporation technique, from previously synthesized bulk samples. The X-ray diffraction showed the amorphous nature for the as-deposited films and the partially crystalline for the annealed films. The optical constants (the refractive index, n, and absorption index k) were determined for as-deposited and annealed Ge1− x Se2Pb x films of different thicknesses by using spectrophotometeric measurements of the transmittance and reflectance at normal incidence in the spectral range 200–2500nm. The obtained values of both n and k were found to be independent of the film thickness. The optical absorption edges are described using both the Urbach rule and the indirect transition. In transparent region, the spectral dependences of refractive index were interpreted in the frame of a single oscillator model. [Copyright &y& Elsevier]

Abstract: In conventional or macroscale milling, appropriate physical vapour deposition (PVD) coatings can be used to improve machining performance, promote the use of higher cutting speeds and facilitate dry machining or the use of minimum quantity lubrication (MQL). When micro tools (1–999μm in diameter) are used in milling, the undeformed chip thickness is usually very small and comparable to the cutting edge radius. This condition determines the effective rake angle and hence plays a significant role in the mechanics of micro machining. The differences between macro and microscale machining influence process factors such as cutting interface temperatures, forces, strains and strain rates. The mechanisms through which coatings protect cutting tools are influenced by such process conditions. Additionally, due to the size of micro tools applying coatings evenly around the cutting edges is a technological challenge. Despite these new challenges, there is hardly any work reported in literature dedicated to the selection of hard coatings for micro machining of tool steels. The work reported in this paper identified coating wear mechanisms in micro milling of hardened tool steels. A wide range of PVD coatings were evaluated based on multiple criteria of tool wear, surface finish and burr size. The results clearly show that compared to other coatings or uncoated fine grain carbide tools, TiN coatings offer the best performance in terms of tool wear reduction and improvement in quality of machined surface. [Copyright &y& Elsevier]

Abstract: Mesoporous alumina layers have attracted attention for their potential use in ultrafiltration of salts, as a heterogeneous catalyst support, an adsorbent in environmental cleanup, and in petroleum refinement. The ability to control the fast hydrolysis rate of the inorganic precursors using simple and inexpensive routes is important for that potential to be realized. Herein, we introduce a novel and facile route to synthesize mesoporous alumina thin films from the combination of inexpensive and commercially available copolymer with aluminum chloride or nitrate (salts) in an EtOH–surfactant–NH3 ·H2O–salts (EsNs) system through the evaporation-induced self-assembly (EISA) method. Mesoporous alumina layers obtained utilizing the EsNs system have ordered and tunable pore structures. The ability to easily control the mesophases of the alumina layers within a short time provides distinct advantages over previously reported synthesis procedures. Most importantly, we demonstrate that the binding of surfactant and NH3 ·H2O for the formation of hydrogen bond between them in the EsNs system controls the fast hydrolysis rate of the inorganic species. This allows for the synthesis of nanocrystalline alumina layers via the aluminum oxo-clusters’ assembly with the surfactant. Such simple route may be applied in the synthesis of other non-silica mesostructured oxides. [Copyright &y& Elsevier]

Abstract: A method to enhance surface plasmon coupled fluorescence (SPCF) from thin copper films using silver islands as an overlayer is presented. Silver islands were deposited onto copper thin films using a wet chemical technique for up to 60s, which resulted in surface features ranging from randomly sized silver nanoparticles to a silver thin film. Theoretical Fresnel calculations predict the coupling of light to copper thin films with a silver overlayer. SPCF and the free-space emission intensities from Rhodamine B spin-coated onto silvered copper were found to be significantly larger than measured from the copper thin films alone. [Copyright &y& Elsevier]

Abstract: This paper presents the results of tensile and high cycle fatigue tests with stress ratio R =0.1 for an Al–3% Ti thin film of 1μm thickness in atmospheric air at room temperature. Specimens with three different widths (50, 100, and 150μm) were fabricated to study the width effects of each sample. Test results show that tensile and fatigue properties for the Al–3% Ti thin film with different widths are very close, and, thus, width effects were found to be minimal. The elastic moduli ranged from 80 to 82GPa, and the tensile strengths ranged from 369 to 379MPa. Fatigue strength coefficients of the specimens with 50, 100, and 150μm width were 193, 181, and 164MPa, respectively. In addition, fatigue strength exponents of the specimens with 50, 100, and 150μm width were −0.023, −0.020, and −0.013, respectively. When present test results are compared with typical properties of bulk aluminium, the Al–3% Ti thin film is found to have longer life at the same stress, but it is more sensitive to the stress level. [Copyright &y& Elsevier]

Abstract: We designed a 5GHz miniaturized 10-pole Chebyshev-type bandpass filter (BPF) using superconducting microstrip quasi-spiral resonators (QSR) for international mobile telecommunication (IMT)-advanced receiving applications. When we considered the unloaded quality factor (Q u) of QSR, we found that a 10-pole QSR BPF using single-sided films and a 17-pole QSR BPF using double-sided films can be achieved an insertion loss in simulation of than 0.5dB. The 10-pole QSR filter was fabricated using a 300nm thick single-sided MgB2 film on a c-sapphire substrate by a thermal co-evaporation method. The Au ground plane of the filter was deposited on the other side of the substrate. Simulation and measurement profile data obtained from the passband were in close agreement. We found that the power-handling performance was equivalent to that of other miniaturized filters. We could design multi-pole filters using QSR. [Copyright &y& Elsevier]

Abstract: We have developed a method using additional electric pads for trimming tunable high-temperature superconducting (HTS) microstrip filters. These filters are generally tuned by adjusting the gap between a dielectric floating plate above the filter. When the floating plate approached the filter, the center frequency was shifted to a lower frequency. However, the insertion loss increases due to variation in the external quality factors varying from the design parameter. The external quality factors are usually controlled by adjusting the length of the input/output (I/O) coupled-line elements and the gap between the elements and the resonator. In our method, additional electric pads are distributed at the open-end of the I/O coupled-line elements of a 3-pole hairpin bandpass filter to enable adjustment of the external quality factors so as to reduce insertion loss. The electric pads consist of line-and-space patterns. They are eclectically connected to the coupled-line elements to adjust the line length and gap width and thereby control the external quality factors. An electromagnetic simulator was used for the design and analysis. The simulation results showed that the additional electric pads are effective in improving the insertion loss of the HTS bandpass filter after tuning. [Copyright &y& Elsevier]

Abstract: HTS dual-mode disk filters tuned by moving an upper dielectric plate which is actuated by a piezo-motor are present. We investigated the effect of the introduced piezoelectric-tunable system on the RF power handling capability of the dual-mode disk filters. The 5GHz-band disk filters with a ground-slot for dual-mode were made from YBCO double-sided films on MgO substrate. At low temperatures, the center frequency shifts of about 270MHz and 430MHz were accomplished with the low-loss, high dielectric LaAlO3 and TiO x plates, respectively. Regardless of the dielectric plates, the power handling capability was improved as the dielectric plates approach to the filter patterns. It is considered that the piezoelectric-tunable system enables to control the superconducting current density of filters. [Copyright &y& Elsevier]

Abstract: We investigated the third-order intermodulation distortion (IMD3) properties of high- temperature superconducting (HTS) filters with sliced microstrip line resonators. Electromagnetic simulations indicated that the current concentration along the outer edges of a sliced microstrip line was lower than that of a conventional microstrip line. We fabricated a 3-pole filter with a sliced microstrip line resonator using HTS YBCO thin films and measured the IMD3. Until the input power increase to 7W, the filter has proper operation from 50 to 77.3K. The third-order intercept point value of 64dBm was observed at 70K. The ΔIMD3 was less than −55 dBc at 1W input power when the temperature was 50–77.3K. The sliced microstrip line indicated low ΔIMD3 to the fundamental two-tone sinusoidal waves, which had a difference of 1MHz, when the input power was 1W. The results showed that HTS filters with sliced microstrip line resonators have better power handling capability and can feasibly be used in transmitters. [Copyright &y& Elsevier]

Abstract: Superconducting MgB2 thin films on the r-Al2O3 substrates have been grown by the combination of radio frequency magnetron sputtering of B and thermal evaporation of Mg, followed by in situ and ex situ annealing. The MgB2 layers had ∼200nm in average thickness and exhibited non-stoichiometry in Mg content. The Mg content in the grown MgB2 layers could be controlled by the temperature of the evaporator and the opening diameter of the shutter. Superconducting transition temperatures have been measured and showed around ∼38K depending on the Mg content and the annealing condition. [Copyright &y& Elsevier]

Abstract: YBa2Cu3O7−x +BaZrO3 +Y2O3 (YBCO+BaZrO3 +Y2O3) mixed films were prepared on SrTiO3/MgO substrates by pulsed-laser deposition from an YBCO+BaZrO3 target with a thin Y2O3 sector stuck on the top. The pinning properties for the double-doped YBCO+BaZrO3 +Y2O3 thin film were enhanced in comparison with a pure YBCO sample prepared in the same experimental conditions. The maximum global pinning forces F P for the double-doped sample are 12.8GN/m3 at 77K, 46.3GN/m3 at 65K, and 122GN/m3 at 40K. In the double-doped sample, the angular dependence of J c showed a broad peak at B//c due to the flux pinning by c-axis correlated defects, combined with a plateau, due to the flux pinning by isotropic pinning centres. Consistently, both BaZrO3 nanorods parallel to the c-axis and Y2O3 nanoparticles randomly dispersed inside the YBCO matrix were observed in TEM images. [Copyright &y& Elsevier]

Abstract: In order to improve a critical temperature (T c) of LaBa2Cu3O y (LaBCO) thin films for achieving a high irreversibility field, we investigated the vapor–liquid–solid (VLS) technique with various composition ratios of Ba/Cu in a liquid layer as growth solvent. As a result, we achieved the VLS-LaBCO thin films with excellent crystallinity and observed a spiral growth consisted of the wide terrace with a width of about 300nm. Moreover, the orthorhombicity and the T c onset of VLS-LaBCO thin films increased with increasing Ba/Cu ratio in the liquid layer. [Copyright &y& Elsevier]

Abstract: In order to achieve high irreversibility field (B irr), we fabricated (Nd, Eu, Gd)Ba2Cu3O y (NEGBCO) thin films by pulsed laser deposition (PLD) method and low temperature growth (LTG) technique. In the LTG–NEGBCO films on MgO, critical current density (J c) at 77K and magnetic field B =5T was 0.13MA/cm2 twice as high as that of PLD–NEGBCO/MgO and B irr at 77K reached 11.8T. Interestingly, the anomalous peaks on the J c–B and F p–B (flux pinning force density F p = J c × B) curves at 77K and B =4T were observed on the LTG–NEGBCO/MgO films. From these results, we can consider that NEGBCO films are good candidates and LTG is an effective technique for improving superconducting properties. [Copyright &y& Elsevier]

Abstract: We have reported novel PVD and MOCVD growth technique, “vapor–liquid–solid growth” and “low-temperature growth (LTG) technique”, for the high superconducting properties and high growth rate. Recently the J c value can be improved by an artificial pinning center (APC) in REBCO film and coated conductor at a magnetic field. Using LTG technique, high J c-SmBCO thick layer and coated conductor in a magnetic field were fabricated with high quality SmBCO-thin seed layer on single crystalline substrate and metal tape. From the surface morphologies and micro structure, we found that LTG is an effective technique for increasing the dislocations without deteriorating crystallinity or superconducting properties. We conclude the dislocations grown at low substrate temperature are effective pinning center in a magnetic field. Furthermore we studied about the crystal growth and pinning mechanism of (Nd/Eu/Gd)BCO films and coated conductor grown by LTG technique for high J c in magnetic fields. In addition SmBCO films with nano-BaZrO3 (BZO) were grown by LTG technique, because BZO rods in PLD–YBCO films have been investigated for flux pinning. [Copyright &y& Elsevier]

Abstract: A new series of ABO3-type REBiO3 have been derived from the system Bi2O3–RE2O3, in which cubic RE2O3 stabilize cubic structure of δ-Bi2O3, enabling the formation of REBiO3 at relatively low temperature range. A chemical solution deposition (CSD) route has been used to deposit epitaxial thin films of REBiO3. The crystal lattice, chemical stability, texture development, combined with the successful deposition of high quality superconducting layer demonstrate that the newly developed compounds may play as potential alternatives of buffer layer materials for REBCO-based coated conductors. [Copyright &y& Elsevier]

Abstract: The overall purpose of this research is to develop a potentially low-cost, high throughput, high yield, manufacturing process for buffer deposition, and to gain a fundamental understanding of buffer layers required for an all metal-organic deposition (MOD) based chemical solution approach. This understanding is critical to the development of a reliable, robust, low-cost, long-length manufacturing process of 2G wires. The standard RABiTS architectures consists of a starting template of biaxially textured Ni–W (5at.%) substrate with a seed layer of Y2O3, a barrier layer of YSZ, and a CeO2 cap. In this three-layer architecture, all the buffers are deposited using reactive sputtering. We have recently demonstrated that the barrier properties and the performance of MOD La2Zr2O7 (LZO) match that of sputtered YSZ layers. In this work, the texture of MOD LZO was also improved by inserting a sputtered Y2O3 seed layer on which LZO grows without any degradation of texture. Significant improvement in the texture of sputtered Y2O3 seeds on NiW substrates is usually observed which is then transferred to the LZO layer. A key challenge for an all-solution approach is to replace the sputtered seed layer with a possible MOD seed layer with improved texture and on which no degradation of LZO texture occurs. Very recently, we have grown MOD La3TaO7 (LTO) seeds directly on biaxially textured Ni–W (3at.%) with improved texture. In this study, we report a systematic investigation of the growth MOD LZO barrier layer on MOD LTO seeds. Preliminary results show that it is possible to grow MOD LZO with improved texture on MOD LTO seeds. This approach could be potentially used for future all MOD buffer/YBCO coated conductors. [Copyright &y& Elsevier]

Abstract: Scandia-stabilized zirconia (SSZ) thin films, ~400 nm thick, were deposited on sapphire substrate by a pulsed-laser deposition (PLD) method. Their structural and transport properties were studied by means of X-ray diffraction and electrical conductivity measurements. The in-plane conductivities of thin films were measured and compared to that of the bulk sample. Although the decrease in ionic conductivity near phase transition temperature (550 °C) was still shown in the case of the 10SSZ film, the conductivity drop was much smaller and less abrupt compared to that of bulk samples. With 1 mol% Y2O3 or CeO2 doping, the conductivity curves became linear. However, the conductivity was reduced from that of the undoped 10SSZ film. [Copyright &y& Elsevier]

Abstract: This work presents an investigation of the role of the nitrogen flow rate on the composition, structure and ionic conductivity of thin films prepared by reactive radio-frequency (rf) sputtering of lithium metaborate targets. It was found that sputtering at constant nitrogen pressure but with increasing nitrogen flow rate leads to thin films with significantly increased nitrogen content. The effect of nitridation on the borate network has been studied by infrared transmittance spectroscopy and revealed boron–nitrogen bonding in triangular arrangements of the glass network, followed by a parallel destruction of borate tetrahedral units. The ionic conductivity of thin films was also measured and found to increase with the nitrogen amount in the film. [Copyright &y& Elsevier]

Abstract: Polycrystalline yttria-stabilized zirconia (YSZ) compacts with a relative density of 97% were prepared by the two-step sol–gel synthesis from zirconium (IV)-propoxide and yttrium chloride. The obtained YSZ compacts were used as polycrystalline substrates for melt-textured YBa2Cu3O7 (YBCO) films. The dense YSZ substrates show a limited reactivity against the highly corrosive Ba/Cu melt and a formation of interlayers with limited thickness between the superconducting film and the substrate can be observed. Crack-free YBCO films with a thickness of about 50μm were prepared by melt infiltration of Ba/Cu melt into the deposited Y2BaCuO5 (211) layer. Since no seeds were used, spherulitic microstructure was formed. The AC magnetization measurements results indicate that the samples are without noticeable weak intergrain links, however, they contain areas with weaker superconducting properties. [Copyright &y& Elsevier]

Abstract: This paper reports the results of an investigation on the performance of the Diffusive Gradient in Thin Films (DGT) Technique in speciation of metals in aqueous samples of municipal wastes and mine effluents. The DGT was assessed regarding its suitability for in situ determination of metal speciation in municipal wastes and aqueous mine effluents. As the thickness of the diffusive gel layer of the DGT was increased to 0.40, 0.80, and 1.60mm, a decrease in the amount of accumulated metal mass was observed for most of the metals studied in all the effluent samples. However, the results were different from one field-study site to another. Effect of kinetics also was observed in the amount of accumulated metal mass by the DGT. The computer speciation code, Windermere Humic Aqueous Model (WHAM VI), was used to predict the metal speciation of Cd, Cu, Ni, Pb, Co, and Zn, and WHAM predictions were compared with those of the experimentally determined metal speciation by the DGT technique (free and labile metal ions). This comparison showed good similarities between the theoretically predicted WHAM VI values and the experimentally measured values by DGT. The DGT technique was found to be simple and useful for investigating chemical speciation of trace metals in aqueous samples of municipal wastes and aqueous mine effluents. [Copyright &y& Elsevier]

Abstract: There has been a debate on the mechanism of resistive switching in Rose Bengal and other Xanthene class molecules. While some authors proposed that the switching was due to an oxide layer at the Rose Bengal/Aluminum interface, some inferred the switching as an extrinsic effect like filament formation. We show results from Rose Bengal and other Xanthene class molecules on doped Si. Conductance switching in such monolayers induced by Pt/Ir tip of a scanning tunneling microscope (STM) in a non-contact mode shows that resistive switching in these molecules, initially reported by us in 2003 (in thin films), is indeed a molecular phenomenon. [Copyright &y& Elsevier]

Abstract: Pentacene-based transistors produced by a novel neutral cluster beam deposition method were characterized, and the effects of the surface pretreatments were examined. Atomic force microscopy and X-ray diffraction showed that the cluster beams were quite efficient in growing high-quality, crystalline thin films on SiO2 substrates at room-temperature without any thermal post-treatment, and that an amphiphilic surfactant, octadecyltrichlorosilane (OTS), enhances the packing density and crystallinity significantly. The observed field-effect mobilities (μ eff) were among the best reported thus far: 0.47 and 1.25cm2/Vs for the OTS-untreated and -pretreated devices, respectively. The device performance was found to be consistent with the estimated trap density and activation energy, which were derived from the transport characteristics for the temperature dependence of μ eff in the range of 10−300K. [Copyright &y& Elsevier]

Abstract: The electrochemical behaviour of thin films of nitrogenated amorphous carbon a-CN x is similar to that of boron-doped diamond, with a wide potential window in aqueous media. They are elaborated by cathodic sputtering of a graphite target in an Ar-N2 active plasma for varying nitrogen contents, determined by XPS (0.06≤ x ≤0.39). Their electrochemical reactivity is sensitive to the surface state. The present study reports on the influence of electrochemical pre treatment on the electronic transfer rate of a fast redox system ferri-ferrocyanide, by focusing on the direction of the potential excursion. On the other hand, the role of both the pH and the potential on the interfacial capacitance in the presence of Na2SO4 without redox species is documented. The results show up the sensitivity of the film surface to the electrochemical conditions. [Copyright &y& Elsevier]

Abstract: FePd thin films were electrodeposited from ammonium citrate complex baths. The effects of various electrodeposition and post heat treatment conditions including pH, current density, bath concentrations, substrates and annealing temperature on composition, material, and magnetic properties were systematically investigated. In these baths, the deposited iron content increased linearly with an increase in current density from 1 to 5mAcm−2 producing films with compositions extending from Fe7Pd93 to Fe91Pd9. Magnetic saturation (M S) of electrodeposited FePd thin films linearly increased with increase in deposited iron content (i.e. ∼1.8T for Fe82Pd18 and ∼0.1T for Fe19Pd81) which is similar to its bulk counterparts. The effects of post-heat treatment on the phase and crystal structure of near equiatomic FePd electrodeposits (i.e. Fe48Pd52) was investigated by subjecting electrodeposits to different annealing temperatures from 400 to 600°C under reducing environment. L10 FePd phase was formed from nanocrystalline FePd solid solution and the crystallinity improved with increasing annealing temperatures. [Copyright &y& Elsevier]

Abstract: NiO thin films have been deposited by chemical spray pyrolysis using a perfume atomizer to grow the aerosol. The influence of the precursor, nickel chloride hexahydrate (NiCl2·6H2O), nickel nitrate hexahydrate (Ni(NO3)2·6H2O), nickel hydroxide hexahydrate (Ni(OH)2·6H2O), nickel sulfate tetrahydrate (NiSO4·4H2O), on the thin films properties has been studied. In the experimental conditions used (substrate temperature 350°C, precursor concentration 0.2–0.3M, etc.), pure NiO thin films crystallized in the cubic phase can be achieved only with NiCl2 and Ni(NO3)2 precursors. These films have been post-annealed at 425°C for 3h either in room atmosphere or under vacuum. If all the films are p-type, it is shown that the NiO films conductivity and optical transmittance depend on annealing process. The properties of the NiO thin films annealed under room atmosphere are not significantly modified, which is attributed to the fact that the temperature and the environment of this annealing is not very different from the experimental conditions during spray deposition. The annealing under vacuum is more efficient. This annealing being proceeded in a vacuum no better than 10−2 Pa, it is supposed that the modifications of the NiO thin film properties, mainly the conductivity and optical transmission, are related to some interaction between residual oxygen and the films. [Copyright &y& Elsevier]

Abstract: Porous Co3O4 nanostructured thin films are electrodeposited by controlling the concentration of Co(NO3)2 aqueous solution on nickel sheets, and then sintered at 300°C for 3h. The as-prepared thin films are characterized by thermogravimetric analysis (TGA), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The electrochemical measurements show that the highly porous Co3O4 thin film with the highest electrochemically active specific surface area (68.64m2 g−1) yields the best electrochemical performance compared with another, less-porous film and with a non-porous film. The highest specific capacity (513mAhg−1 after 50 cycles) is obtained from the thinnest film with Co3O4 loaded at rate of 0.05mgcm−2. The present research demonstrates that electrode morphology is one of the crucial factors that affect the electrochemical properties of electrodes. [Copyright &y& Elsevier]

Abstract: The hydrothermal synthesis of anatase-type TiO2 films on Ti and Ti–Nb substrates was examined with a focus on crystallinity and surface morphology of the films. The substrates were chemically treated with H2O2/HCl or H2O2/HNO3 solution to prepare amorphous-like TiO2. The hydrothermal treatment of the resultant films was performed in an autoclave with deionized water or NH3 aqueous solution. The synthesized anatase-type TiO2 films showed high crystallinity and rectangular morphology. The (Ti, Nb)O2 film could be obtained by using Ti–Nb alloys as substrates. [Copyright &y& Elsevier]

Abstract: When used at oblique angles of incidence, the reflectance and transmittance of thin films exhibit strong polarization effects, particularly for the films inside a glass cube, which results from the fact that the tangential components of the electric and magnetic fields are continuous across each layer interface. However, for many applications, the polarization effects are undesirable and should be reduced. In the present paper, a method for designing a non-polarizing beam splitter (NPBS) in a cube is introduced, based on the Brewster condition. Applied examples of the NPBSs designed employing this method are also researched within specified wavelength ranges. Moreover, the effects of some important parameters, including the incident angle and the material indices, on the NPBS are investigated. Optical property simulations are presented. [Copyright &y& Elsevier]

Abstract: The Pt–Pd and Pd–Ag nanostructured bimetallic films on porous α-Al2O3 substrates are successfully synthesized by chemical deposition using lyotropic liquid crystalline templating strategy. The co-reduction of two metallic species in the presence of liquid crystalline phase by hydrazine hydrate produces hexagonal nanostructured Pt–Pd and lamellar nanostructured Pd–Ag films. Low-angle X-ray diffraction (XRD) and transmission electron microscopy (TEM) studies show the ordered nanostructure of both Pt–Pd and Pd–Ag films. The energy dispersive X-ray (EDX) and wide-angle XRD analyses of the bimetallic films have verified the coexistence and uniform distribution of constituent metallic species. By taking into account of catalytic activities, well-defined nanochannels and higher surface areas, the nanostructured bimetallic films might have application potential in microreactors. [Copyright &y& Elsevier]

Abstract: The Bi4Ti3O12 (BTO) thin film were fabricated on an n-type Si substrate and annealed by rapid thermal annealing methods. The temperature dependence of capacitance–voltage (C–V) and conductance–voltage (G/ω–V) characteristics of the Au/Bi4Ti3O12/SiO2/n-Si metal–ferroelectric–insulator–semiconductor (MFIS) structures was investigated by taking the effects of series resistance (R s) and interface states (N ss) in the temperature range of 80–400K. Both the density of interface states N ss and series resistance R s were found to be strongly temperature dependent. It is observed that the C–V and G/ω–V plots exhibit anomalous peaks at forward bias because of the influences of N ss and R s. It has been experimentally determined that these peak positions shift from accumulation to inversion region, and the maximum values of the capacitance (C) and conductance (G) generally increase with temperature. Also, the distribution profile of R s–V shows a peak in the accumulation region. The effect of R s on the C and G is more pronounced in the studied temperature range. The experimental C–V–T and G/ω–V–T characteristics of MFIS structures show the expected behavior due to N ss in equilibrium with the semiconductor. The temperature dependent C–V and G/ω–V characteristics confirm that the R s and N ss play an important role and strongly affect the electrical parameters of MFIS structure. [Copyright &y& Elsevier]

Abstract: Nanocrystalline ZnS thin films are prepared on glass and quartz substrates by sulfurizing ZnO thin films in the H2S-containing mixture at 500°C. These films are investigated by X-ray diffraction, scanning electron morphology, optical transmittance and photoluminescence spectra. The results show that the ZnS thin films have the hexagonal structure with a c-axis preferred orientation. Also, these nanostructure ZnS thin films with the grain size of ∼50nm along the c-axis, exhibit the optical transparency as high as ∼80% in the visible region. It is found that sulfur replacement of oxygen sites in crystal lattices and recrystallization can take place during sulfidation, resulting in an evident increase of the grain size for the sulfurized films. Under the optimum sulfidation time of 2h, the resultant ZnS thin films have a high crystallinity, low defect concentration and good optical properties with the band gap of 3.66eV. [Copyright &y& Elsevier]

Abstract: The investigation of Al2O3 etch characteristics in the BCl3/Ar inductively coupled plasma was carried out in terms of effects of input process parameters (gas pressure, input power, bias power) on etch rate and etch selectivity over poly-Si and photoresist. It was found that, with the changes in gas pressure and input power, the Al2O3 etch rate follows the behavior of ion current density while the process rate is noticeably contributed by the chemical etch pathway. The influence of input power on the etch threshold may be connected with the concurrence of chemical and physical etch pathways in ion-assisted chemical reaction. [Copyright &y& Elsevier]

Abstract: The temperature dependence of photoluminescence (PL) efficiency in fluorescent dye-doped tris(8-hydroxyquinoline)aluminum (Alq3) layers and blended Alq3 layers was investigated. Results show that the PL efficiency in the fluorescent dye-doped Alq3 layers has only weak temperature dependence, which is in contrast to the dramatic decrease of PL efficiency observed upon increasing temperature for undoped Alq3. This phenomenon is attributed to the narrower energy bandgap of the dopant, as compared to that of Alq3, which leads to the ‘trapping’ of mobile excitons on dopant molecules, hence impeding their migration by thermally activated diffusion, thereby decreasing their encounters with randomly distributed non-radiative recombination (i.e. quenching) sites. [Copyright &y& Elsevier]

Abstract: In2S3 layers have been grown by close-spaced evaporation of pre-synthesized In2S3 powder from its constituent elements. The layers were deposited on glass substrates at temperatures in the range, 200–350°C. The effect of substrate temperature on composition, structure, morphology, electrical and optical properties of the as-grown indium sulfide films has been studied. The synthesized powder exhibited cubic structure with a grain size of 63.92nm and S/In ratio of 1.01. The films grown at 200°C were amorphous in nature while its crystallinity increased with the increase of substrate temperature to 300°C. The films exhibited pure tetragonal β-In2S3 phase at the substrate temperature of 350°C. The surface morphological analysis revealed that the films grown at 300°C had an average roughness of 1.43nm. These films showed a S/In ratio of 0.98 and a lower electrical resistivity of 1.28×103 Ωcm. The optical band gap was found to be direct and the layers grown at 300°C showed a higher optical transmittance of 78% and an energy band gap of 2.49eV. [Copyright &y& Elsevier]

Abstract: Barium tin titanate Ba(Sn0.15Ti0.85)O3 (BTS) thin films with (100), (110) and (111) orientation were grown on (100), (110) and (111) LaAlO3 (LAO) single-crystal substrates through sol–gel process, respectively. The in-plane dielectric properties of the films were measured on interdigital capacitor (IDC). Films with the (111) orientation had larger relative dielectric constant and larger tunability against the dc bias electric field than (100)- and (110)-oriented films. This difference in dielectric properties in these three kinds of oriented BTS films may be attributed due to change in the direction and magnitude of electric polarization in orientation engineered BTS films. This work clearly reveals the dielectric properties of BTS films exhibited a strong sensitivity to crystal orientation. [Copyright &y& Elsevier]

Abstract: Zeolite L thin films were fabricated by applying fine zeolite L seed crystals on glass substrates and then hydrothermally treating the seeded substrates in reaction sols. The influence of anisotropic growth of the seed crystals on the orientation of the films was examined. The reaction sols were prepared by mixing KOH, Al, colloidal silica, and water. With increasing the amount of the KOH in the sols or with decreasing the hydrothermal temperature, the zeolite L crystals obtained from the sols changed from a rod-like shape to a clam-like one, indicating a decrease in the relative rate of the growth along the c-axis of zeolite L with a hexagonal lattice to one normal to the c-axis. For the film fabricated at a small amount of KOH or at a high hydrothermal temperature, the c-axis of the zeolite crystals was oriented normal to the substrate. The fabrication at a large amount of KOH or at a low hydrothermal temperature led to films consisting of zeolite crystals whose c-axis is parallel to the substrate. When the aspect ratio of the precipitated crystals decreased to about one, the c-axis of the zeolite crystals in the films became parallel to the substrate. [Copyright &y& Elsevier]

Abstract: A simple convergent procedure has been developed for the preparation of triphenylamine dendrons containing an alkene at the center, which can be coupled in a single step to give dendrimers that contain truxene for the core without any protection–deprotection chemistry. These conjugated dendrimers exhibit similar absorption and emission behaviors in solutions and in thin films, which are indicative of the high isolation effect of well-organized three-dimensional dendrimers. They also have high fluorescence quantum yields and high glass transition temperatures, which indicate that these dendrimers are candidates for the application in OLED as light emitting materials. [Copyright &y& Elsevier]

Abstract: This work presents the influence of annealing on the structure and stoichiometry of europium (Eu)-doped titanium dioxide (TiO2). Thin films were fabricated by magnetron sputtering from a metallic Ti–Eu target in oxygen atmosphere and deposited on silicon and SiO2 substrates. After deposition the selected samples were additionally annealed in air up to 1070 K. Film properties were examined by means of X-ray diffraction (XRD), atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS) and the results were analyzed together with the undoped TiO2 thin films prepared under similar technological conditions. XRD results showed that depending on the Eu content, as-deposited thin films consisted of the TiO2-anatase or TiO2-rutile. An additional annealing will result in the growth of anatase crystals up to 35nm, but anatase to rutile phase transformation has not been recorded. AFM images display high quality and a dense nanocrystalline structure. From the XPS Ti2p spectra the 4+oxidation state of Ti was confirmed. The O1s XPS spectra displayed the presence of an O2− photoelectron peak accompanied by an additional broader peak that originates from hydroxyl species chemisorbed at the sample surface. It has been found that Eu dopant increases the OH− content on the surface of prepared TiO2:Eu thin films. The calculated O/Ti ratio was in the range of 1.85–2.04 depending on the sample. [Copyright &y& Elsevier]

Abstract: In this work, we have chosen oxidation of TiN thin films as a feasible method for preparation of nitrogen-doped titanium dioxide thin films, TiO2:N, for photocatalytic applications. DC reactive magnetron sputtering with the plasma emission control was used for deposition of stoichiometric TiN thin films. The microstructure and chemical composition of films before and after oxidation were investigated by means of RBS, X-ray diffraction (XRD) in grazing incidence diffraction (GID) configuration, AFM and XPS techniques. The electrical conductivity was measured by the van der Pauw method as a function of the oxidation temperature. The optical transmittance and reflectance spectra of the films were measured over the visible and UV ranges of the light spectrum. GID diffraction patterns of as-sputtered TiN thin films and those after oxidation indicate that TiO2 rutile is formed at around 300°C. Nitrogen is still present as indicated by XPS studies even when XRD detects the rutile only. Optical absorption of thin films oxidized at 450°C is shifted towards the visible range of the light spectrum. [Copyright &y& Elsevier]

Abstract: Undoped and Pd-doped SnO2 films were deposited at various substrate temperatures and discharge gas pressures using reactive magnetron sputtering. Structural factors of the films, such as crystallite size, grain size, and film density, were systematically investigated. The main objectives of this study are to clarify the operation temperature dependence of the H2 sensitivity of these films as well as to clarify the dominant structural factor in the determination of the sensitivity. The operation temperature at which the sensitivity defined by (R a−R g)/R g, where R a and R g are the resistances before and after exposure to H2, showed a maximum decreased with decreasing film density. The highest sensitivity of 4470 was obtained for a Pd-doped film with the lowest density of 3.1 g/cm3 at 100 °C. It was found that the sensitivity correlated with film density rather than with crystallite size and grain size. The high sensitivity of a Pd-doped porous film at a low temperature was discussed in relation to the Schottky-barrier-limited transport as well as the chemical and electronic effects of Pd. [Copyright &y& Elsevier]

Abstract: Increasing the alignment of thin films, which leads to anisotropy, is an attractive way to improve the performance of organic devices. A highly controllable and reproducible method to fabricate organic field effect transistors with large anisotropic ratios was proposed in this paper. The surface of the dielectric layer was etched to form patterns through conventional semiconductor processing. Transistors having current direction perpendicular to or parallel to the direction of the patterns were fabricated and characterized. The mobilities of these two kinds of transistors are 0.016 and 0.001 cm2/Vs respectively, which means the anisotropic ratio is 16. [Copyright &y& Elsevier]

Abstract: The synthesis and optical properties of the 5,5′,6,6′-tetraphenyl-2,2′-bi([1,3]dithiolo [4,5-b] [1,4]dithiinylidene)–2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) complex thin film were investigated by the optical characterization. The optical constants such as refractive index, extinction coefficient and absorption coefficient were determined using the transmittance T(λ) and reflectance R(λ) spectra and the refractive index dispersion was analyzed using single oscillator of Wemple–Didomenico model. The single oscillator energy E 0 and the dispersion energy E d were calculated. The effect of temperature on refractive dispersion and optical band gap E g is also discussed. As a result, the annealing temperatures have an important effect on refractive index of thin film. [Copyright &y& Elsevier]

Abstract: Top-contact thin film transistors with ZnO as the channel layer and thermally grown SiO2 as the gate dielectric were fabricated by using rf sputtering. The performances of ZnO-TFTs with different thicknesses of the active layer were investigated and the optimized condition was obtained. With the active layer thickness from 25 to 70 nm, the leakage current of devices increased from 10−10 to 10−8 A, and the on/off ratio decreased from 1.2×107 to 2×104. Atomic force microscope research indicated that with the thickness increased, the surface morphology of the active layer improved noticeably at first and then deteriorated. The 25-nm-thick ZnO TFT had the best surface morphology, and showed the best performance with a field effect mobility of 5.1 cm2/V S, on/off ratio of 1.2×107 and threshold voltage of 20 V. This indicates that the surface properties of the channel layer have crucial affects on the performances of ZnO-TFTs. [Copyright &y& Elsevier]

Nanoporous gold thin films were prepared by dealloying and were completely crack-free, with a continuous ligament network across grain boundaries. Film stress increases during dealloying, and thermal cycling causes thermoelastic deformation. Ligament width coarsens during cycling to 200°C, but at higher temperatures the porous structure densifies. The stability of nanoporous films may also depend on film thickness. From the biaxial film stress, the equivalent yield strength of nanoporous gold was calculated to be at least 1.8GPa. [Copyright &y& Elsevier]