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Anti reflection coating with high hardness on the OLED display surface was studied to improve the wear resistance and visibility of OLED. However, the high residual stress inside the multilayer thin film configuration of anti reflection coating has been a problem and the improvement is necessary. In this study, the residual stress and optical properties variation on various deposition conditions on the thin film were investigated. In addition, we suggested new coating structure using nanocomposites to overcome the residual stress of films. [ABSTRACT FROM AUTHOR]

We investigated the structural, optical, and electrical properties of molybdenum and zirconium-doped zinc oxide (ZZO) with a purity of 99.99% deposited on a glass substrate by radio-frequency magnetron sputtering and annealed at different temperatures. The doping amount of zirconium on ZnO was 3 wt%. The optimal resistivity of the multilayers, 5.1 x 10-3 Q-cm, was observed for an annealing temperature of 400 °C. This film also had the highest transmittance of 93%. Moreover, the optimal figure of merit, 4.6 x 10-6 Ω-1, was observed for an annealing temperature of 400 °C. Furthermore, the grain size also increased with the annealing temperature, as observed by scanning electron microscopy. Mo/ZZO multilayer thin films with such excellent optical and electrical properties can be applied in photosensors. [ABSTRACT FROM AUTHOR]

Leakage currents in InAlN/GaN‐based high‐electron‐mobility transistors considered for normally‐off devices critically depend on the oxidation behavior of InAlN thin films. Herein, lattice‐matched InAlN thin films deposited on GaN (0001) are rapid thermally annealed at 800 °C in an oxygen‐rich environment. Aberration‐corrected scanning transmission electron microscopy combined with electron energy‐loss spectroscopy is used to systematically characterize the oxidation behavior of InAlN films as a function of annealing time. Initial growth of oxide layers is found to be reaction limited, which is replaced by a diffusion limited growth process once a critical thickness of the oxide layer is obtained. Growing oxide layers are amorphous and become porous with increasing annealing time. [ABSTRACT FROM AUTHOR]

Detailed dynamic modeling of a solar sail requires recording of solar radiation pressure influence. A photon-solar sail is determined by the thrust value and the direction. We define the solar sail's reflectivity depending on the film materials, the sail design and temperature, the thickness of multiple layers, and degradation factor, with a reasonable degree of accuracy. Thus, this work is devoted to the identification of optical characteristics of thin multilayer films in space flight conditions, i.e. to finding its reflectance, absorbance, and transmittance. In particular, the paper asks whether the solar sail simulates by a mathematical model of the optical characteristics of a multilayer epitaxial thin film. The temperature change effect and optical properties of solar sail degradation are considered as well. Solar sail flight from Earth to Mercury is designed as a simulation of the flight change in optical parameters. [ABSTRACT FROM AUTHOR]

• Multilayers of poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) and Cu 2 Se through a facile route. • Structural investigation shedding light over transport properties. • A higher power factor value which is about 82 % higher than that of pure PEDOT:PSS. Cu 2 Se is a promising thermoelectric material due to its superionic behavior with superior transport properties. Here we report a facile method of spin coating for the fabrication of multilayers of poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) and Cu 2 Se thermoelectric materials for mid-temperature range applications. The synthesis of multilayered thin films with a unique organic-inorganic hybrid framework could be used in flexible thermoelectric devices. The detailed investigation of PEDOT:PSS and Cu 2 Se multilayered thin films reveals interaction between organic and inorganic material as inferred by AFM and FTIR. The electronic transport properties were investigated for all specimens, with the highest PF of 20.1 µW/m. K2 at 450 K was achieved from the bilayer stacking of Cu 2 Se and PEDOT:PSS, which is about 82 % higher as compared to that of pure PEDOT:PSS at the same temperature. These improved transport properties are the combined effect of energy filtering and interface effects. The proposed strategy opens up an avenue for research on chalcogenide based composite materials with an organic framework for flexible thermoelectric device applications. [ABSTRACT FROM AUTHOR]

• Mercapto-propionic acid was grafted onto PPFS by para-fluoro-thiol reaction. • The extent of modification of PPFS was tuned by the reactional parameters. • The ability of PPFS-based copolymers to develop H-bonds with P4VP was studied. • H-bonded LbL films were successfully prepared. • The growth mechanism of the LbL assembly was fully investigated. Para-fluoro-thiol reaction (PFTR) was applied to poly(2,3,4,5,6-pentafluorostyrene) (PPFS) with mercaptopropionic acid (MPA), resulting in a library of carboxylated-PPFS copolymers (PPFS-MPA) differing in their chemical composition. The ability of these COOH-containing derivatives to develop H-bonds with poly(4-vinyl pyridine) (P4VP) in solvent solution was investigated, and it was shown that the extent of the H-bonded complexes was closely influenced by the degree of PPFS modification and by the nature of solvent. Subsequently, the Layer by Layer stepwise deposition of P4VP and PPFS-MPA was achieved from various deposition solvents. It was demonstrated that the use of DMF as solvent does not allow for the formation of LbL films, due to its competitive H-bond acceptor character. In contrary, when solvents such as CHCl 3 and MEK are respectively utilized for P4VP and PPFS-MPA, thick (P4VP/PPFS-MPA)-based LbL films constituted of interpenetrated layers are obtained and the topography is smooth and rather featureless. The use of ethanol as deposition solvent for both P4VP and PPFS-MPA leads to very thin films made of well-stratified polymer layers, with a nodular and patchy surface morphology. [ABSTRACT FROM AUTHOR]

Abstract This paper investigates the influence of thermal annealing temperature on the periodic nanostructures and the thermoelectric properties of Sb 2 Te 3 /Au multilayer thin films fabricated by magnetron sputtering. The as-deposited amorphous periodic multilayer films (10 periods, 20 and 7 nm for the Sb 2 Te 3 and Au layers, respectively) show regular and sharp interfaces between Sb 2 Te 3 and Au layers. It was found that the interfaces of periodic films became a little fuzzy and some nanocrystallines could be observed after annealing at relatively lower temperature (373 K) due to atomic diffusion and crystallization. Additionally, obvious crystal grains appeared and the Au layers began to coarsen and even rupture when the annealing temperature was elevated to higher than 423 K. The evolution mechanism has been discussed in the view of grain boundary free energy and interfacial free energy. Furthermore, the experimental results suggest that the resistivity and Seebeck coefficient of the multilayer film sample have not exhibited distinct change until the annealing temperature was increased to as high as 473 K when the periodic nanostructures disappeared. Graphical abstract Image 1 Highlights • Nice periodic layered nanostructure in as-deposited multilayer film. • The Au layers began to coarsen and rupture when annealing at 423 K. • Stable layered structure and thermoelectric performance at lower temperature (below 423 K). [ABSTRACT FROM AUTHOR]

The multiphase coexisting of compositionally graded PbZr x Ti 1- x O 3 multilayer thin films were fabricated using sol-gel method. The giant electrocaloric effect (ECE) has been obtained through regulating the growth sequence of the multilayer thin films. At room temperature (at 298 K), Δ T values of up graded multilayer and down multilayer thin films are 9.1 K (applied electric field E = 755 kV/cm) and 7.3 K ( E = 930 kV/cm), respectively. In addition, both of the films exhibit outstanding ECE at higher temperature, Δ T values of 17.9 K (at 453 K) and 26.8 K (at 393 K) are also obtained for up graded multilayer and down multilayer thin films. The results indicate that the compositionally graded multilayer thin films with a giant ECE could be a potential candidate for the application in cooling devices. [ABSTRACT FROM AUTHOR]

Nanocelluloses are promising high gas barrier materials for biobased food packaging, but they must be protected from water to preserve high performance. The respective O 2 barrier properties of different types of nanocelluloses were compared (nanofibers (CNF), oxidized nanofibers (CNF TEMPO) and nanocrystals (CNC)). The oxygen barrier performance for all types of nanocelluloses was similarly high. To protect the nanocellulose films from water, a multilayer material architecture was used with poly(lactide) (PLA) on the outside. To achieve this, a biobased tie layer was developed, using Corona treatment and chitosan. This allowed thin film coating with nanocellulose layers between 60 and 440 nm thickness. AFM images treated with Fast Fourier Transform showed the formation of locally-oriented CNC layers on the film. Coated PLA(CNC) films performed better (3.2 × 10−20 m3.m/m2.s.Pa) than PLA(CNF) and PLA(CNF TEMPO) (1.1 × 10−19 at best), because thicker layers could be obtained. The oxygen barrier properties were constant during successive measurements at 0 % RH, 80 % RH and again at 0 % RH. This shows that PLA is sufficiently shielding nanocelluloses from water uptake to keep high performance in an extended range of RH and opens the way to high oxygen barrier films which are biobased and biodegradable. [Display omitted] [ABSTRACT FROM AUTHOR]

Polyelectrolyte multilayer (PEM) thin film composed of weak polyelectrolytes was designed by layer-by-layer (LbL) assembly of poly(allylamine hydrochloride) (PAH) and poly(methacrylic acid) (PMA) for multi-drug delivery applications. Environmental stimuli such as pH and ionic strength showed significant influence in changing the film morphology from pore-free smooth structure to porous structure and favored triggered release of loaded molecules. The film was successfully loaded with bovine serum albumin (BSA) and ciprofloxacin hydrochloride (CH) by modulating the porous polymeric network of the film. Release studies showed that the amount of release could be easily controlled by changing the environmental conditions such as pH and ionic strength. Sustained release of loaded molecules was observed up to 8 h. The fabricated films were found to be biocompatible with epithelial cells during in-vitro cell culture studies. PEM film reported here not only has the potential to be used as self-responding thin film platform for transdermal drug delivery, but also has the potential for further development in antimicrobial or anti-inflammatory coatings on implants and drug-releasing coatings for stents. [ABSTRACT FROM AUTHOR]

A multilayer film architecture has been investigated as a means to stabilize the morphology and electrical conductivity of Pt-based nanocomposite films that are exposed to temperatures up to 1200 °C in air. The multilayer architecture consists of a 150 nm thick conducting Pt-alloy electrode inserted between a 10 nm thick adhesion layer and a 50 nm thick protective capping layer on sapphire or langasite substrates. The Pt-alloy films were fabricated by e-beam co-evaporation of a Pt or Pt 83 Rh 17 source and a range of different alloying elements (Co, Ni, Cr, Rh, Ta, Ti, Nb, Al, Sn) or oxides (HfO 2 , ZrO 2 , Nb 2 O 3 , Y 2 O 3 , RuO 2 , CeO 2 , NiO, CoO, MnO 2 ). Second phase inclusions or interlayers within the Pt-alloy films provide grain boundary pinning and hinder agglomeration of Pt grains, resulting in films that retain conductivities > 1 × 10 6 S/m after annealing in air. Pt–Al 2 O 3 , Pt–HfO 2 , and nanolaminate Pt–Ni/Pt–Zr films performed the best, remaining conductive after annealing to 1050–1150 °C. For Pt–Rh/HfO 2 films, adhesion layers of Ni, Zr, Y, and CeO x yielded the highest film stability temperature. Capping layers of ZrO 2 or Y 2 O 3 did not significantly improve the film stability. Electrically conducting films that remain stable above 1000 °C in oxidizing high temperature environments have potential applications as electrodes in a wide range of technologies, including microwave acoustic sensors, MEMS devices, and fuel cells. [ABSTRACT FROM AUTHOR]

Abstract: This work demonstrates a simple and feasible method to construct magnetic and luminescence nanospheres for drug delivery. Fe3O4@SiO2 core–shell structure nanospheres were firstly prepared, the matrix films capable of loading and release of anionic molecules were then successfully deposited on the surface of the Fe3O4@SiO2 nanospheres via a layer-by-layer (LbL) assembly method by using luminescence microgels (named FITC-PAHD) and chondroitin sulfate (CS) as building blocks and verified by ultraviolet visible and photoluminescence measurements, transmission electron microscopy and fluorescence microscopy. The model drug ibuprofen was loaded into the Fe3O4@SiO2@(FITC-PAHD/CS)4 nanospheres because of the electrostatic interaction of ibuprofen with amine groups in the FITC-PAHD microgels via ion exchange. Ibuprofen loaded in the nanospheres can be released in 0.9% normal saline in a sustainable way for 12days and the Fe3O4@SiO2@(FITC-PAHD/CS)4 nanospheres have a maximum uptake amount of ibuprofen of 117mg·g−1. The magnetic and luminescence nanospheres with high loading capacity are expected to be widely useful as carriers for drug delivery followed by magnetic separation and luminescent detection. [Copyright &y& Elsevier]

The structural features of the distribution of Pd and Fe atoms in multilayer films derived via Penning-discharge sputtering are studied. The preparation of films is a highly nonequilibrium process; at the same time, it is relatively simple in terms of possible structural implementations, which are shown during the self-organization of sputtered atoms through the formation of clusters with an individual ordered structure. It is important that the 'dynamic chaos' that appears during sputtering is stabilized during crystallization, which makes it possible to study the resulting structures using nondestructive inspection methods with fairly wide possibilities. Therefore, it is of interest to study self-organization during the sputtering of multilayer films in order to reveal the mechanisms of cluster formation and to simulate them. It is also shown that the self-organization during sputtering and subsequent crystallization is accompanied not only by the ordering in the form of clusters, buts also by an ordered arrangement of these clusters. [ABSTRACT FROM AUTHOR]

Abstract: Two kinds of nanocomposite ultrathin films, i.e., (Ag@keratin/PDDA) n and (keratin/PDDA) n +Ag(0) nanoparticles (NP), have been fabricated by layer-by-layer (LbL) deposition and in situ deoxidization method, respectively. The assembling process was monitored by means of UV–vis spectroscopy. Scanning electron microscope (SEM) was used to observe the surface morphology and thickness of the multilayer films. The distribution of silver NP within the two LbL films were evaluated by transmission electron microscope (TEM) measurement. It was found that (Ag@keratin/PDDA) n films present superior fluorescent properties that that of (keratin/PDDA) n +Ag(0) NP. TEM results suggest that the fusion of the small silver clusters (which is fluorescent) is hindered in the direct LbL assembly, while larger Ag NP are formed by the in situ preparation. The corrosion-resistance of the Ag@keratin/PDDA multilayer films against the acid and basic etching solution is also tested. [Copyright &y& Elsevier]

Abstract: In this paper a ZnS/Ag/ZnS (ZAZ) nano-multilayer structure is designed theoretically and optimum thicknesses of ZnS and Ag layers are calculated at 35 and 17nm, respectively. Several conductive transparent ZAZ nano-multilayer films are deposited on a glass substrate at room temperature by thermal evaporation method. Changes in the electrical, structural, and optical properties of samples are investigated with respect to annealing in air at different temperatures. High-quality nano-multilayer films with the sheet resistance of 8Ω/sq and the optical transmittance of 83% at 200°C annealing temperature are obtained. The figure of merit is applied on the ZAZ films and their performance as transparent conductive electrodes are determined. [Copyright &y& Elsevier]

Abstract: A glucose-sensitive multilayer film was fabricated by the layer-by-layer (LbL) assembly method with positively charged 21-arm poly[2-(dimethylamino)ethyl methacrylate] (star PDMAEMA) and negatively charged insulin and glucose oxidase (GOD) in the form of {(Star PDMAEMA/Insulin)4 + (Star PDMAEMA/GOD)4 + Star PDMAEMA}. The multilayer film shows an on-off regulation of insulin release in response to stepwise glucose challenge in vitro. It is found that the unique structure of star PDMAEMA and interdiffusion of charged insulin are the main factors to control the on-off status of the film. Reversible surface morphology transitions of the multilayer film were also observed, revealing a phase separation and large-scale reorganization process. Furthermore, the multilayer film could continuously release enough insulin in vivo after being subcutaneously implanted in streptocozotin-induced diabetic rats and reduce the blood glucose level for at least two weeks. It is indicated that such system may have substantial potential as a glucose-sensitive carrier for insulin due to its distinct mechanism. [Copyright &y& Elsevier]

Abstract: Depending on the resistivity and transmittance, transparent conductive oxides (TCO) are widely used in thin film optoelectronic devices. Thus doped In2O3 (ITO), ZnO, SnO2 are commercially developed. However, the deposition process of these films need sputtering and/or heating cycle, which has negative effect on the performances of the organic devices due to the sputtering and heat damages. Therefore a thermally evaporable, low resistance, transparent electrode, deposited onto substrates room temperature, has to be developed to overcome these difficulties. For these reasons combination of dielectric materials and metal multilayer has been proposed to achieve high transparent conductive oxides. In this work the different structures probed were: MoO3 (45nm)/Ag (x nm)/MoO3 (37.5nm), with x =5–15nm. The measure of the electrical conductivity of the structures shows that there is a threshold value of the silver thickness: below 10nm the films are semiconductor, from 10nm and above the films are conductor. However, the transmittance of the structures decreases with the silver thickness, therefore the optimum Ag thickness is 10nm. A structure MoO3 (45nm)/Ag (10nm)/MoO3 (37.5nm) resulted with a resistivity of 8×10−5 Ωcm and a transmittance, at around 600nm, of 80%. Such multilayer structure can be used as anode in organic solar cells according to the device anode/CuPc/C60/Alq3/Al. We have already shown that when the anode of the cells is an ITO film the introduction of a thin (3nm) MoO3 layer at the interface anode (ITO)/organic electron donor (CuPc) allows reducing the energy barrier due to the difference between the work function of ITO and the highest occupied molecular orbital of CuPc [1]. This property has been used in the present work to achieve a high hole transfer efficiency between the CuPc and the anode. For comparison MoO3/Ag/MoO3/CuPc/C60/Alq3/Al and ITO/MoO3/CuPc/C60/Alq3/Al solar cells have been deposited in the same run. These devices exhibit efficiency of the same order of magnitude. [Copyright &y& Elsevier]

Abstract: Light scattering losses from dielectric multilayer are becoming increasingly important for designing high precision performance optical devices. In this paper, we applied the bi-directional reflectance distribution function of optical multilayer and analyzed the total reflectance scattering losses based on both the completely correlated and non-correlated interface models to compare with a high reflection 17-layer optical multilayer deposited on roughness of 2.8nm substrates. The experimental result supports the completely correlated interface model as firstly the wavelength dependence is in good agreement with the phase change of the calculated result and secondly the calculated scattering intensity of the completely correlated interface scattering model is approximately the same as that of the measured scattering spectrum, while the intensity using the non-correlated interface scattering model is significantly higher than the measured result in the high transmission ranges and lower in the main band of the high reflection range. [Copyright &y& Elsevier]

• Indium tin oxide (ITO) based multilayer films on p-silicon substrate were prepared. • 9 nm Cu and 6 nm Al metals interlayer inserted between two 37 nm ITO layers. • Sheet resistance of 3.26 Ω/sq, high figure of merit of 92.47 × 10−3 Ω−1 achieved at 600 °C. • Excellent rectifying contact with 0.71 eV barrier height obtained at 600 °C. The distinguished transparent conductive indium tin oxide (ITO) based multilayer films with thin copper-aluminium (Cu-Al) metals interlayer (ITO/Cu-Al/ITO) were prepared on p-type silicon (Si) by radio frequency and direct current magnetron sputtering methods. The ITO/Cu-Al/ITO (ICAI) films structural, topological, optical and electrical properties coupled with electronic properties of ICAI/p-type Si interface were investigated at different post annealing temperature up to 600 °C. Despite the inclusion of Cu-Al metals interlayer, structural analysis results yielded an amorphous structure for the as-deposited films. The films become polycrystalline with a cubic bixbyite structure after post annealing treatment. Dominant In 2 O 3 (222) and Cu (111) peaks intensities were observed at 500 °C and 600 °C indicating substantial enhancement in the films crystallinity at high moderate temperatures. The ICAI films reveal a smooth surface roughness with improved growth in grain size after post annealing treatment as examined by microscopic equipment.The films optical transmittance promptly increased from 73.2% (for as deposited film) to 88.7% (for annealed film at 600 °C) at 470 nm in the visible region with increasing post annealing temperature. The film annealed at 600 °C exhibits excellent electrical characteristics with a very low electrical resistivity of 2.44 × 10−5 Ω cm and sheet resistance of 3.26 Ω/sq. The ICAI films optoelectronic properties as calculated by figure of merit (FOM) show outstanding performance at 600 °C with a high FOM of 92.47 × 10−3 Ω−1 in spite of the reduced ITO films thickness. In addition, admirable ICAI/p-type Si interface quality was observed after post annealing treatment (at 600 °C) as indicated by current-voltage characteristics results. These improved ICAI multilayer films can be favourable for silicon heterojunction solar cells and other low resistance optoelectronic applications. [ABSTRACT FROM AUTHOR]

RuL2+3 (L = 2,2′-bipyridine-4,4′-diphosphonic acid) thin solid films were fabricated by three-dimensional linking between the phosphonic acid substituents of L and Zr(O)Cl2. The RuL3 chromophores in the films are electronically independent of each other in the ground state and give emission spectra essentially identical to that of RuL2+3 in solution, although the emission lifetime is much shorter. The films are electrochemically active, showing pseudo-reversible oxidation behavior in cyclic voltammetry. A preliminary attempt has been made to apply these films to photoelectrochemical cells. [ABSTRACT FROM AUTHOR]

Abstract: The paper analyses the equivalent circuit corresponding to two consecutive planar diffusion layers of finite thickness (porous Warburg or O elements) present in an electrochemical system. This case often occurs in important systems, such as protective coatings or membranes, which are routinely studied using electrochemical impedance spectroscopy (EIS). Relations are obtained that connect the diffusion impedance of a multilayer to the impedances of individual layers and also take into account partitioning effects. It is shown that the equivalent circuit that correctly represents the total diffusion impedance (e.g., for use in EIS spectra fitting algorithms) consists of several O and T (bounded Warburg) elements connected in a complex way. Analysis of limiting cases shows that the low-frequency limiting behavior of a multilayer film may significantly differ from those of individual layers showing asymmetry and synergism. In particular, it is shown that a thin layer of solution between an electrode and a resistant film to be characterized may seriously interfere with the measurements. [Copyright &y& Elsevier]

Abstract: Silver nanocomposite multilayer films were prepared through the in situ method. Multilayer thin films, prepared through the sequential electrostatic deposition of a positively charged third-generation poly(amidoamine) dendrimer (PAMAM) and negatively charged poly(styrenesulfonate) (PSS) and poly(acrylic acid) (PAA), were utilized as nanoreactors for the formation of silver nanoparticles. The silver ions were preorganized in layer-by-layer (LBL) films composed of PAMAM dendrimers and subsequently reduced with hydrogen to prepare the silver nanoparticles. The UV–vis spectrum and profilometer were used to characterize the regular growth of bilayers. UV–vis absorption from plasmon resonance at 435 nm and TEM images indicated the formation of the silver nanoparticles in the multilayer films. The silver nanocomposite LBL films were also constructed on the indium tin oxide-glass and investigated using cyclic voltammetry. The silver nanoparticles in the multilayer films have a stronger negative redox potential. The silver nanocomposite LBL films may have a potential application in the catalysis of reduction of 4-nitrophenol with sodium borohydride. [Copyright &y& Elsevier]

Abstract: In this work is reported the growth of multilayered composite Au-NiOx films by sputtering, using different deposition pressures that allow varying the Au content inside the oxide matrix. The films were characterized by RBS, XRD, TEM, cyclic voltammetry and spectral transmittance measurements. The films present anodic electrochromism, and those containing Au show a selective absorption in the green region of the visible spectrum in the bleached state, which was observed after the intercalation/deintercalation process. Au reduction process occurs during electrochemical cycling. [Copyright &y& Elsevier]

The assembly of multilayer films of gelatin onto glass substrates using layer-by-layer and lift-off (LbL-LO) technology to modify the surface topography and chemistry properties of in vitro cell culture scaffolds is described. The ability to generate such nanoscale systems containing cell-adhesive materials on optically transparent substrates with microscale lateral dimensions, nanoscale vertical dimensions, molecular vertical precision, and flexibility in material selection has important implications for tissue engineering, drug discovery, and basic research in cell biology. Toward this goal, a systematic study on the electrostatic adsorption properties of fluorescein 5-isothiocyanate-gelatin B (FITC-gelatin) was completed. In addition, the integration of protein nanoassembly with microlithographic feature definition was used to pattern three-dimensional FITC-gelatin nanofilms on planar glass substrates. The experimental results indicate that FITC-gelatin is negatively charged at pH 9 and can be alternately assembled with a positively charged polyion, poly(diallyldimethylammonium chloride) (PDDA), to form multilayer films on solid templates with thickness of 5-10 nm per bilayer. Furthermore, images of protein/polymer nanocomposites indicate that LbL-LO is an efficient way to realize the designed substrates. These findings will benefit future research on cell culture and tissue engineering that require methods of generating protein patterns to fabricate novel in vitro cell culture systems. [ABSTRACT FROM PUBLISHER]

High-quality multiplayer (ML) ferroelectric thin films based on erbium-doped lead titanate Pb(1−x)1.1ErxTi1−x/4O3 (PET) where x=0.05 and Pb1.1(Zr0.58Fe0.2Nb0.2Ti0.02)O3 (PZFNT) have been processed via chemical solution deposition on textured (1 1 1)Pt/Ti/SiO2/Si substrates. The dielectric, ferroelectric and pyroelectric properties are being characterised. It is shown that the multilayer film exhibits the relaxor type behaviour found for pure PZFNT, and that its transition temperature of 310 °C at 1 kHz lies between those of PET and PZFNT. The dielectric constant of 520 also lies between those of PET and PZFNT. The ferroelectric properties are considerably improved over those of the monomorph films. An unusually high pyroelectric coefficient of approximately 620 μC m−2 K−1 was obtained from measurements of the temperature dependence of the remnant polarisation between 30 and 80 °C. The voltage and current responses measured using a modulated near IR-laser, could be improved by 2–3 orders of magnitude over those of PZFNT. The thermal time constant τT obtained is found to be 3 orders of magnitude lower than the electrical time constant τE, and indicates that the high thermal conduction rate in the substrate determines the detector responsivity. [Copyright &y& Elsevier]

In this paper, a ZnS/Ag/ZnS multilayer system for the transparent electrodes in flat panel displays was designed. The optical and electrical performance of an Ag and ZnS single layer films with nano-dimensions was investigated. The smallest thickness of the continuous single layer Ag film that could be deposited on SiO2 surface by thermal evaporation is approximately 12 nm. The spectroscopic ellipsometry analysis indicated that the interlayer between the Ag and ZnS layer contains a physically mixed layer and a compound semiconductor layer. Based on these studies, according to the characteristic matrix theory, the design for the optimized system was carried out with complete searching strategy. A group of the optimized structures with good selective filtering performance were successfully prepared, including some new extremely asymmetric multilayer structures. These have low sheet resistance of 3 Ω/□ and a good spectral selectivity performance with luminous transmittance Tlum approximately 90% and the reflectance near infrared region above 90%. The figure of merit FTC used for evaluating transparent electrodes reached 7.3×10−2 at 550 nm wavelength. [Copyright &y& Elsevier]

Epitaxial multilayer thin films of NdBa2Cu3O7−δ/NdBa2TaO6/NdBa2Cu3O7−δ (NBCO/NBTO/NBCO) have been in situ grown on (100) SrTiO3 substrate by pulsed laser deposition with the aim of investigating the suitability of using NBTO as an interlayer for Josephson junction devices. NBTO, a dielectric ceramic material, has a cubic perovskite structure (A2BB′O6) and is reported to have good chemical compatibility with 123 Superconductors. The structural characterisation of the films was carried out by θ–2θ and four axis X-ray diffraction. The θ–2θ X-ray scans of the multilayer films showed that both NBCO and NBTO films were (0 0 l) oriented and the φ-scan X-ray diffraction patterns revealed that the films were having excellent in-plane orientation. The temperature-resistance measurements of the top NBCO film gave a Tc(0) of 91.5 K with a transition width of 0.5 K. Our results indicate that NBTO is a potential dielectric interlayer material for its use in NBCO superconductor multilayer structures for electronic device applications. [Copyright &y& Elsevier]

Antiferroelectrics are famous for their unique electric field-induced phase transition polarization behavior, which have a wide application in the fields of power electronics and electrical engineering. In this work, Al 2 O 3 and PbZrO 3 films are chosen as the insulator and antiferroelectric, respectively, and the multilayer thin films are fabricated by chemical solution method. The microstructure and electrical performances are systematically investigated. The results demonstrate that antiferroelectric-insulator multilayer films exhibit remarkable ferroelectricity which may be induced by the self-polarization effect. The constructed PbZrO 3 /Al 2 O 3 bilayer films accompany an amazing remanent polarization of 43 μC/cm2, and the PbZrO 3 /Al 2 O 3 /PbZrO 3 trilayer films possess excellent energy storage performance. The values of recoverable energy storage density of 32.6 J/cm3 and efficiency of 88.1% are obtained for trilayer films annealed at 550 °C, meaning that the design of antiferroelectric-insulator multilayer structure is an effective approach to regulate polarization behaviors and enables the films to have excellent energy storage performances. [Display omitted] • PbZrO 3 /Al 2 O 3 antiferroelectric/insulator multilayer films have been constructed for the first time. • The PbZrO 3 /Al 2 O 3 multilayer films exhibit remarkable ferroelectricity. • The recoverable energy storage density of 32.6 J/cm3 and efficiency of 88.1% have been obtained. [ABSTRACT FROM AUTHOR]

Abstract: Photoluminescence property of the nanoparticles synthesized by laser annealing of Si nanoparticles and C60 thin films, which were fabricated by pulsed laser ablation, was investigated. C60 thin films were deposited on two types of substrates, which were Si (p-type 111) and sapphire (R-plane). The C60 thin films were verified to have a far smoother surface than that of films produced by the conventional evaporation method. The roughness of the C60 thin film was about 0.38nm of RMS. Then Si nanoparticles were fabricated on the C60 thin film. The Si nanoparticles deposited at He pressure of 0.2Torr were about 60Å in height. We observed a green photoluminescence spectrum from the Si/C60 multilayer films after laser annealing. Raman data revealed that this green photoluminescence was generated from the Si1− x C x particles, which were produced in the reaction of the Si nanoparticles with the C60 via laser annealing. [Copyright &y& Elsevier]