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Broadband unity absorption in graphene-insulator-metal (GIM) structures is demonstrated in the visible (VIS) and near-infrared (NIR) spectra. The spectral characteristics possess broadband absorption peaks, by simply choosing a stack of GIM, while no nanofabrication steps and patterning are required, and thus can be easily fabricated to cover a large area. The electromagnetic (EM) waves can be entirely trapped and the absorption can be greatly enhanced are verified with the finite-difference time-domain (FDTD) and rigorous coupled wave analysis (RCWA) methods. The position and the number of the absorption peak can be totally controlled by adjusting the thickness of the insulator layer. The proposed absorber maintains high absorption (above 90%) for both transverse electric (TE) and transverse magnetic (TM) polarizations, and for angles of incidence up to 80°. This work opens up a promising approach to realize perfect absorption (PA) with ultra-thin film, which could implicate many potential applications in optical detection and optoelectronic devices. [ABSTRACT FROM AUTHOR]

Abstract: An Al2O3-modified aluminide coating was produced by aluminizing an as-electrodeposited Ni–Al2O3 nanocomposite film using pack cementation method at 1100  C for 4 h. For comparison, aluminizing was also performed in the same condition on an as-deposited Ni film without Al2O3 nanoparticles. SEM/EDAX and TEM results indicated that the co-deposited Al2O3 nanoparticles were homogeneously dispersed in the finer-grain nanocrystalline Ni grains. The isothermal and cyclic oxidation in air at 900 °C indicated that the Al2O3-modified aluminide coatings were profoundly oxidation resistant as compared to the Al2O3-free aluminide coatings due to the faster formation of a continuous adherent α-Al2O3 scale. The effect of Al2O3 on the microstructure and the oxidation of the aluminide coating are discussed in the detail. [Copyright &y& Elsevier]

Abstract: The microstructural defects of nanocrystalline SnO2 thin films prepared by pulsed laser deposition have been investigated using transmission electron microscopy, high-resolution transmission electron microscopy and Raman spectroscopy. Defects inside nanocrystalline SnO2 thin films could be significantly reduced by in situ annealing SnO2 thin films at 300°C for 2h. High-resolution transmission electron microscopy showed that the stacking faults and twins were annihilated upon in situ annealing. In particular, the inside of the SnO2 nanoparticles demonstrated perfect lattices free of defects after in situ annealing. Raman spectra also confirmed that the in situ annealed specimen was almost defect-free. By using in situ annealing, defect-free nanocrystalline SnO2 thin films can be prepared in a simple and practical way, which holds the promise for applications as transparent electrodes and solid-state gas sensors. [Copyright &y& Elsevier]

Abstract: Investigations of growth of RuO2 thin layer on Ru by oxidation were performed by means of scanning tunneling microscopy (STM). The results showed that the morphologies and the structures of RuO2 thin film grown on Ru depend crucially on the O2 pressure and reaction temperature. At a sample temperature of about 600K and an O2 pressure of 5×10−6 mbar, the oxidation of Ru leads to formation of Ru–O chain structures, which can be attributed to the dynamical hindrance arisen from the repulsive dipolar interaction. This dynamical hindrance can be overcome, and the RuO2(100)-(1×1) phase, together with the RuO2(100)-c(2×2) patch, can be formed by increasing O2 pressure. Further increasing the sample temperature up to 760K at the same O2 pressure, the oxidation results in formation of a RuO2(111) film over the RuO2(100) thin layer. [Copyright &y& Elsevier]

Abstract: The Sb-doped TiO2 thin films were prepared on glass by RF magnetron co-sputtering method. The influence of Sb element and calcination temperature on the films structure was investigated by XRD, XPS, and AFM. The antibacterial activity against Escherichia coli bacteria was studied applying the antibacterial drop-test. The bactericidal activity for the bacteria cells was estimated by relative number of bacteria survived calculated from the number of viable cells which from colonies on the nutrient agar plates. The Sb-doped TiO2 thin films exhibited a high antibacterial activity, which was enhanced with the increase of the temperature of thermal treatment and formation of anatase crystalline structure. [Copyright &y& Elsevier]

Abstract: Shape memory thin films offer a unique combination of novel properties, which promise some exciting application potentials in micro-electromechanical systems (MEMS). In this study, Ti48.9Ni46.3Cu4.8 (at.%) driving thin films were successfully prepared by radio-frequency magnetron sputtering. Crystallographic structure, surface morphology and phase transformation temperatures were investigated by X-ray diffraction, scanning electron microscopy, atomic force microscope and differential scanning calorimeter, respectively. Applying a MEMS process, a valve-less micropump of Ti48.9Ni46.3Cu4.8 shape memory thin film for low temperature application is fabricated. The results show that the phase transformation between martensite and austenite is rather low, below 290K, and the surface of the thin films is smooth. The displacement measurement clearly revealed the TiNi(Cu) diaphragm valve-less pump has superior performance such as high diaphragm displacement (up to 6μm) and high working frequency (up to 85Hz). [Copyright &y& Elsevier]

Abstract: Epitaxial growth of PbSe thin film on is studied by means of scanning tunneling microscopy (STM). The results showed that the structures and morphologies of PbSe thin films depend crucially on Pb-to-Se atomic ratio in the growth of PbSe film. For the PbSe film grown with an atomic ratio of at a substrate temperature of , the morphologies are dominated by two interlocked spirals around threading dislocation. Meanwhile, for the PbSe film grown with a higher Pb-to-Se atomic ratio, besides some spirals structures, the V-defects appear in the film. PbSe growth on is in the step-flow mode, and the formation of the V-defects in the case of the PbSe film growth with a higher Pb-to-Se atomic ratio can be attributed to excessive Pb atoms congregating in the dislocation core area and relatively slow growth rate of facets. [Copyright &y& Elsevier]

Abstract: Thin film growth of tetracene on Ag(110) has been investigated by using scanning tunneling microscopy (STM). In the monolayer regime, the tetracene molecules formed islands of ordered structure, which is commensurate (4-fold periodicity) in the direction, but incommensurate in the [001] azimuth, with the substrate. All the tetracene molecules align regularly with their longer axes parallel to the [001] direction, and with their molecular planes parallel to the surface. At multilayer coverages, the tetracene molecules form a crystalline film in a novel 3D orthorhombic structure, with their orientations remained unchanged. Growth of tetracene on Ag(110) is in the layer-by-layer growth mode. [Copyright &y& Elsevier]

Abstract: X-ray photoelectron spectroscopy has been used to examine the chemical nature of titanium nitride (TiN) films deposited by reactive unbalanced magnetron sputtering under different substrate biases (ranging from 0 to -500V). Before Ar+ sputtering, three groups of Ti 2p doublet, related to TiN, TiON and TiO2, were observed in the core level spectra of the deposited TiN films. The intensity of peak from TiO2 decreases drastically with the increasing substrate bias, reaching a minimum at a bias voltage of –100V, and then increases greatly. However, the intensity of peak from TiN shows an opposite behavior with its maximum value at –100V. Furthermore, the nonlinear intensity variation of these peaks was accompanied with obvious nonlinear trend of peak shift. Similar tendency was found for the N 1s spectra of these films. After Ar+ sputtering, the Ti 2p and N 1s region of bulk TiN both displayed a nonlinear peak shifting with their highest binding energy at a bias voltage of –50V. The reason for the different optimum bias between the surface and the bulk were considered to be the incorporation and diffusion of oxygen near surface. The appropriate substrate bias was believed to be helpful for the bonding and formation of stoichiometric TiN, hinder the generation of surface oxide and restrict the initiation of impurities and defects in both surface and bulk materials. Our atomic force microscopy study also revealed a nonlinear trend of surface morphology and root-mean-square roughness. As a combined effect from improved surface morphology, significantly restricted surface oxidation and well-bonded stoichiometric TiNx in both native surface and bulk material, the best hardness was measured to be about 32GPa at optimum bias of –100V. [Copyright &y& Elsevier]

Abstract: A CeO2-dispersed aluminide coating was fabricated through aluminizing the electrodeposited Ni–CeO2 nanocomposite film on carbon steel using pack cementation method at 700 °C for 4 h. The isothermal and cyclic oxidation behavior of the CeO2-dispersed aluminide coating at 900 °C, including the growth of oxide scale and the microstructure of the coatings, have been investigated comparing with the aluminide coating on carbon steel. The results show enhanced oxidation performance of the CeO2-dispersed aluminide coating, which is concerned with not only CeO2 effect on the microstructure and oxidation, but also decreased interdiffusion between the aluminide and the Ni film. The CeO2 benefit effects and interdiffusion are discussed in detail. [Copyright &y& Elsevier]

Abstract: The epoxy-based anisotropic conductive film (ACF) joints have the potential of being exposed to a hygrothermal environment and susceptible to moisture sorption. The long-term hygrothermal aging will induce the irreversible damages of epoxy resins system due to susceptibility of the polymer to hydrolysis, oxidation, etc. In this study, the hygrothermal environment test was used as an accelerator for the degradation of ACF joints in Chip-on-Glass (COG) assemblies. The effects of aging on the adhesion strengths were measured by shear mode tests and the changes of molecular conformation were analyzed by Fourier Transform Infrared Spectroscopy (FTIR). Results show that the ACF adhesion strengths decrease with aging and there are some chemical modifications to the aged ACF joints. [Copyright &y& Elsevier]

Abstract: We present a photochemical method for the laser directed deposition of silver thin films, through the illumination of a low power laser in a solution containing citrate and silver ions. With this method silver can be laser-directed to be deposited on a number of surfaces, such as metals, semiconductors, polymers and composites. In this study, we investigate the effects of applied light dosage (time variation) and chemical concentration of a precursor on the thin film deposits to support a proposed mechanism on the nucleation and growth of such Ag films and to outline the different conditions under which surface nucleation will be favoured. With this method, Ag can be selectively deposited by low power laser and has the potential to form maskless direct-write metallic periodic patterns via optical interference. [Copyright &y& Elsevier]

Novel hybrid thin films covalently doped with Eu3+ (Tb3+) have been prepared via direct routes involving co-condensation of tetraethoxysilane and phen-Si in the presence of Eu3+ (Tb3+) by spin-casting and their luminescence properties have been investigated in detail. Lanthanide ions can be sensitized by anchored phenanthroline in hybrid thin films. Excitation at the ligand absorption wavelength (272 nm) resulted in the strong emission of the lanthanide ions i.e. Eu3+ 5D0–7FJ (J=0, 1, 2, 3, 4) emission lines and Tb3+ 5D4–7FJ (J=6, 5, 4, 3) due to the energy transfer from the ligands to the lanthanide ions. [Copyright &y& Elsevier]