Search

Recently, transparent ultraviolet (UV) photodetectors have gained wide attention for their giant potential in integrated transparent electronics applications. SnO2 films as a common candidate for visible-blind transparent ultraviolet photodetectors have attracted increasing attention. In this work, high-performance visible-blind transparent UV photodetectors based on SnO2 thin film and a SiO2 passivation layer were successfully synthesized by the sol–gel spin coating method for the first time. The obtained SnO2/SiO2 hybrid device has a transmittance of nearly 80% in the visible band at 400–700 nm and demonstrates a high responsivity of 769 mA W−1 and a detection sensitivity of 1.24 × 1014 Jones under UV light illumination. The UV-C/UV-A rejection ratio is greater than 106, indicating that the device has good photo-selectivity. In addition, after the introdution of the SiO2 layer, the response speed is 2 times higher than that of pure SnO2. The presence of the SiO2 layer reduces the exposed area of SnO2, passivates the oxygen vacancies on the surface of SnO2 and inhibits the surface chemical adsorption. The above results provide a new perspective for improving the performance of SnO2 thin film for visible-blind transparent ultraviolet photodetectors. [ABSTRACT FROM AUTHOR]

Infrared (IR) antireflective and protective coating (ARPC) is crucial for the development of IR precision guidance and detection systems for practical applications, attracting significant attention from strong military powers worldwide. Extreme application environments require functional film to have high surface hardness, excellent stability, and good adhesion. Further, multispectral optical transmission demands extremely low absorption in the visible and far‐IR bands, adjustability of optical performance parameters, and optical antireflection in particular bands, and radar stealth requires a relatively low resistance. Herein, recent experimental progress on IR ARPC is reviewed and future opportunities are discussed. Based on the application environment and window substrate, various ARPC material systems, including diamond‐like C, Ge carbide, B phosphide, and oxides, have been developed. These systems are capable of fulfilling different application demands and demonstrate exciting application prospects. To promote the development of IR ARPC material technology, the basic characteristics, fabrication techniques, microscale structures, optical properties, mechanical properties, and development and applications of typical IR ARPC materials from a comprehensive and systematic perspective are presented. [ABSTRACT FROM AUTHOR]

• A new P-type transparent conductive LaSe 2 film with excellent photoelectric properties is found. • A novel two-step method is used to prepare LaSe 2 film. • Effect of annealing time on their photoelectric properties is investigated. • Results indicate that the best annealing time is 2 h. LaSe 2 films were prepared on sapphire (0001) substrates by combining magnetron sputtering and selenized annealing. The influence of selenized annealing time on the structures and photoelectric properties of the thin films were investigated using glancing incident X-ray diffraction, fourier transform infrared spectrometry and Hall effect measurements. The results showed that the film had a perfect monoclinic structure and a smooth surface morphology. The average transmittance in the mid-infrared range was greater than 55%, and the highest was 65%. The LaSe 2 films had a higher carrier concentration (∼1019 cm−3) and conductivity (∼1.9 S/cm) than those of other P-type transparent conductive films, which showed that LaSe 2 was a potential new P-type material. [ABSTRACT FROM AUTHOR]

Abstract As lanthanum oxide (La 2 O 3) has a large bandgap, it exhibits excellent optical properties. In this work, La 2 O 3 thin films are prepared by the sol-gel method from a lanthanum chloride (LaCl 3) precursor, on quartz and sapphire (0001) substrates. The effect of the annealing temperature (400–800 °C) on the optical properties of the La 2 O 3 films is investigated. The structure and optical properties are analyzed by X-ray diffraction, atomic force microscopy, scanning electronic microscopy, X-ray photoemission spectroscopy, Raman spectroscopy, ultraviolet (UV)–visible spectroscopy, Fourier transform infrared spectroscopy, and infrared variable angle spectroscopic ellipsometry. Results indicate that with an annealing temperature of ~600 °C, the roughness and optical properties of La 2 O 3 films can be significantly improved. Highlights • La 2 O 3 thin films are prepared by sol-gel method on quartz and sapphire substrates. • Effect of annealing temperature on their optical properties is investigated. • Results indicate that the best annealing temperature is around 600 °C. • The roughness and optical properties of films are significantly improved. [ABSTRACT FROM AUTHOR]

Abstract Transparent electronic technology has many urgent optoelectronic device applications. A key component of plasmonic materials in conventional semiconductors is the wide band gap of oxide thin films. Although transparent electronic materials have been developed for visible and near-infrared wavelengths, systems incorporating mid-infrared and far-infrared spectra are difficult to achieve. In this study, hydrated magnesium-carbon films, a new type of non-oxide transparent conductive thin films with a magnesium hydroxide structure, were generated using the three-step method. After annealing treatment, larger crystals in the thin films typically exhibited superior film resistivity, with conductivity values of approximately 8.63 × 10−3 Ω m. Due to the free electron concentration was not more than 1020 cm−3, the films demonstrated excellent optical properties, with plasma wavelength values of approximately 8 μm for infrared transmittance above 70%. After annealing, due to the Moss-Burstein (M-B) effect, the visible light transmittance was greater than 85% and the optical bandgap shifted towards the blue region. In addition, the influences of the sputtering power of the carbon target on the properties of hydrated magnesium-carbon film were also discussed in this paper. Graphical abstract Image 1 Highlights • We prepare hydrated magnesium-carbon films using the three-step method. • We analyze the effect of annealing on structural, electrical, and optical features. • Annealing leads to crystal growth, superior film resistivity, and good conductivity. • Films exhibit excellent optical properties, particularly for far-infrared ranges. • The films can replace TCO in the application of optical-electronic devices. [ABSTRACT FROM AUTHOR]

Abstract High-quality, transparent, conducting, p-type γ-CuI thin films are prepared via an innovative layer-by-layer procedure based on the traditional simple iodination of Cu films (referred to as the LBL-I method) at room temperature (RT). The structure, morphology, and optoelectronic properties of the γ-CuI are investigated as functions of the per layer thickness. The final thicknesses of LBL-I γ-CuI films are consistent with that in the film prepared by the traditional one-step method (TOS). X-ray diffraction analysis reveals that all the films are polycrystalline with the most dominant (111) direction of the zinc blende structure, indicating the facile and successful fabrication of γ-CuI. Compared with the TOS film, the LBL-I films display enhanced transmittance and mobility. The higher transmittance of >80% in the visible region of LBL-I films was attained due to the smaller root-mean-square roughness values of 23–28 nm. The 50 nm/ l LBL-I CuI films have mobility values of 6.9–9.4 cm2 V−1 s−1, and lower resistivity of 0.039–0.05 Ω cm, which assist studies on applications of γ-CuI thin films in transparent electronics. Highlights • High-quality electrooptical properties p-type γ-CuI thin films are prepared. • Innovative layer-by-layer approach based on Cu films iodination (LBL-I) is used. • LBL-I films show better transmittance and mobility than films prepared in one step. [ABSTRACT FROM AUTHOR]

Abstract In p-type γ -CuI thin films synthesized by the iodination of Cu layers with iodine vapor, a frosted-glass-like appearance with a rough surface is usually obtained, which makes it difficult to apply the γ -CuI films to transparent electronics. This paper proposes an innovative method for the preparation of highly transparent p-type γ -CuI films. A chemical reaction between Cu thin films and iodine vapor, combined with the layer-by-layer process at a temperature between room temperature and 120 °C are found to result in highly transparent polycrystalline γ -CuI films. The root-mean-square roughness values of the γ -CuI films prepared by this method are 8.5–21.2 nm, which are smaller than those for the γ - CuI films synthesized by the conventional method. The microstructure and optoelectronic properties of the γ-CuI thin films are sensitive to the temperature of iodine vapor. A high transmittance (80%) of the film obtained at an iodine vapor temperature of 80 °C has a low resistivity of 5 × 10−2 Ω cm and high mobility of 8.7 cm2/Vs. Moreover, a boosted figure of merit is realized due to the simultaneously low resistivity and high transparency: its value jumps from ∼488 to ∼1630 MΩ−1. Graphical abstract Unlabelled Image Highlights • A traditional iodination reaction method combined with the layer-by-layer process. • Simultaneously high transmittance and low resistivity. • A boosted figure of merit is realized. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A novel two-step method is developed to grow 2D Mg(OH) 2 nanoflakes. • The proposed method is environmentally benign. • The method does not require catalysts or harsh acid-base conditions. • The Mg(OH) 2 films had a crystalline hexagonal structure is dominant. • The water contact angle of 139° showed the good hydrophobicity of the film. Abstract A novel and environmentally benign two-step method has been developed to grow 2D magnesium hydroxide (Mg(OH) 2) nanoflakes. Our method relies on the deposition of Mg films by magnetron sputtering, followed by reaction with water vapor, and does not require any catalyst or harsh acid-base conditions. The 2D nanoflake surface morphology with a crystalline hexagonal structure was dominant on the Mg(OH) 2 films. The water contact angle on the film was ∼139°, which testified the good hydrophobicity of Mg(OH) 2 films due to the nanoflake surface. The self-cleaning effect of contaminant particles on hydrophobic Mg(OH) 2 films was analyzed. Compared with other preparation methods, this two-step method is more efficient, cleaner, and simpler, which make it suitable for complex or large-area substrate surfaces. In addition, this method can be applied to other metal hydroxides or oxides. [ABSTRACT FROM AUTHOR]

The hydrated magnesium-carbon films fabricated in this study are the novel-innovative non-oxide-type transparent electronic material. The films, which have a structure similar to that of magnesium hydroxide, were produced by making Mg x -C y films deposited by magnetron co-sputtering react with water vapor. As the extrinsic defect of hydration magnesium-carbon films, C atoms provided redundant electrons, resulting in a conductivity of approximately 3.31 × 10 −2  Ω·cm. Although the conductivity of hydrated magnesium-carbon films is not prominent comparing to the conventional and widely-used n-type TCO materials, e.g. ITO, the films also showed excellent optical properties, which can be attributed to their low bond energy, with the infrared transmittance of the films being greater than 72% for a plasma wavelength of approximately 10 μm. By varying the atomic C content of the films, a visible-region transmittance greater than 80% could be realized. The optical bandgap of the films was approximately 4.04–6.87 eV and was blue-shifted because of the Moss-Burstein effect. [ABSTRACT FROM AUTHOR]

The non-contact feature of the Laser/EMAT ultrasonic (LEU) technique is attractive for its NDT applications. However, it is challenging to apply it in thin structures because of the difficulties in the signal interpretations. In this work, the LEU technique is used to inspect the notch depths in thin steel plates. A Continuous Wavelet Transform (CWT)-based algorithm is developed to calculate the transmission coefficients of laser-generated Lamb waves. The effect of varying notch depths on Lamb waves’ transmission coefficients is investigated both numerically and experimentally. The transmission coefficients of laser-generated Lamb waves calculated using CWT have been used successfully to predict the notch depths in thin structures. [ABSTRACT FROM AUTHOR]

A novel plasma exposure technique has been introduced into conventional magnetron sputtering process to enhance the crystallization of indium oxide (InO) films at room temperature. The effect of plasma exposure technique with different pulsed DC voltages on the electrical and mechanical properties of InO films was investigated. It is observed that film crystallization can be significantly enhanced when the pulsed DC voltage (| V|) is higher than |−500 V| (| V| > |−500 V|). By applying the plasma exposure process, InO films prepared at room temperature with thickness of 135 nm shows low resistivity of 4.11 × 10 Ω cm, mobility of 42.1 cm/Vs, and transmittance over 80 % in the visible range. Compared with the InO films without plasma exposure process, the InO films with plasma exposure show better crystallization and remarkably higher nanohardness. The plasma exposure technique is a useful candidate technique for enhancing film crystallization at low temperature. [ABSTRACT FROM AUTHOR]

Highlights: [•] Y2O3:Ru (RYO) films were prepared on ZnS substrates by reactive magnetron sputtering. [•] Ru doping significantly decreases the resistivity and extends the transparent range. [•] Optical and electrical properties of RYO films can be tuned by substrate temperatures. [•] The RYO films exhibit excellent far-IR transmittance and electrical property. [ABSTRACT FROM AUTHOR]

Abstract: Ni–Cu–P alloy film of 4.0wt%Cu and 10.1wt%P was deposited on Cu substrate through pulse electroplating. Microstructures, morphologies and phases of the alloy films were studied. Phase transformation kinetics of the alloy films during the DSC annealing was also investigated. The results show that the as-deposited Ni–Cu–P alloy film is composed of an amorphous Ni(Cu,P) matrix in which 5nm spherical Ni(Cu) grains are embedded. After the alloy film annealed at 673K, Ni5P2 precipitates from the amorphous matrix; and at 773K, Ni5P2 transforms into Ni3P, which is spherical and about 10nm in diameter. Meanwhile, the nanocrystalline Ni(Cu) grains grow up to be regular hexagon and 60–70nm in diameter. The activation energies related to the precipitation of Ni5P2 from the Ni(Cu,P) matrix and the phase transformation of Ni3P from Ni5P2 were deduced to be 178.3 and 238.4kJmol−1, respectively. [Copyright &y& Elsevier]

Abstract: Thin films of La0.85Sr0.15MnO3 (LSM) are deposited on (100) silicon wafer and YSZ (yttria-stabilized zircornia) electrolyte substrates by magnetron sputtering using a single-phase LSM target. The conditions for sputtering are systematically studied, including substrate temperature (from room temperature to 600°C), the argon background pressure (from 1.2×10−2 to 3.0×10−2 mbar), and deposition time. Results show that the optimal conditions for producing a dense, uniform, and crack-free LSM film include a substrate temperature of 600°C and an argon pressure of 1.9×10−2 mbar. Further, a testing cell with a dense LSM film, an YSZ electrolyte membrane, and a porous LSM counter electrode is prepared and the electrochemical properties of the dense LSM film on YSZ substrate are studied. It was found that the thickness, morphology, and microstructure of LSM films critically influence the electrochemical properties. [Copyright &y& Elsevier]

Abstract: Uniform and porous Al coatings on FeCrAl substrate were prepared using an efficient electrophoretic deposition (EPD) in absolute ethanol suspension. The zeta potential and viscosity of suspension were measured to determine the optimal AlCl3·6H2O concentration for deposition. The most homogeneous coatings were obtained with 0.5mM AlCl3·6H2O as the electrolyte. The effects of applied voltage and deposition time on deposition rate and coating morphology were also investigated. Uniform coatings could be obtained by EPD at 30V within 2min. By characterizing the Al deposition kinetics, it was found that the deposition rate was mainly determined by the current density after initial deposition period. A porosity equation was also proposed, indicating that the porosity of uniform coatings could be easily manipulated by deposition voltage. In this way, different Al coatings can be designed and prepared by EPD according to the practical requirement. [Copyright &y& Elsevier]

NiCrAl–Al oxidation resistant coatings on nickel foams were for the first time prepared by electrophoretic co-deposition with a simple consolidation treatment. NiCrAl–Al coated nickel foams showed much more satisfactory oxidation and bending resistance than NiCrAl coated and bare nickel foams. This might be attributed to the compact composite coatings after both deposition and thermal treatment. The Al addition could ensure the formation of continuous and thick α-Al2O3 layers on the surface and inhibit the diffusion of Cr into the substrate during oxidation. [Copyright &y& Elsevier]

A framework for the numerical solution of the Landau-Lifshitz-Gilbert equation is developed in this paper. The numerical framework is based on the finite element method on tetrahedral meshes for the spatial discretization and the implicit midpoint scheme for the temporal discretization. The computational complexity for calculating the demagnetization field is effectively reduced by using a PDE approach, in which a gradient recovery technique is used for preserving the numerical accuracy. The numerical convergence of the proposed method is studied in detail for the μ MAG standard problem #3, from which a limit is predicted for the desired side length. The capability of the proposed method on handling problems defined on complex domains is successfully demonstrated by several examples, in which the computational domains are thin films with irregular defects. [ABSTRACT FROM AUTHOR]

Vanadium pentoxide (V 2 O 5) films were deposited on sapphire substrates by radio frequency (R.F.) magnetron sputtering at 450 °C and annealed in various ambient atmospheres. The influence of ambient atmospheres on the structure, optical properties, and morphology of the thin films after annealing were characterized, and the transition behaviors in the annealing process were investigated by DSC, temperature-dependent Raman and FTIR. The results demonstrated that V 2 O 5 films underwent four different transition behaviors during post-deposition annealing due to the different oxygen proportion of ambient. Different products (VO 2 (B), VO 2 (R)) in the transition process were the main reason for the evolution of optical properties. No transition behaviors occurred because of the oxygen-rich ambient when annealed in air, and no significant change in infrared transmittance was observed. When annealed in 0.1% O 2 /Ar, the film was converted to VO 2 (B) with the decrease of infrared transmittance. In the case of 0.01% O 2 /Ar, metastable VO 2 (B) and VO 2 (R) were observed as intermediate crystalline phases before V 2 O 5 finally transformed to VO 2 (M), and the changes in the three stages of two drops and one rise were shown in infrared transmittance. While annealed in pure argon ambient, V 2 O 5 was turned into VO 2 (R) and VO 2 (M) without VO 2 (B) phase production, accompanied by a single change of infrared transmittance reduction and recovery. This provides a more detailed vanadium oxide thermal transition process and shows data reference for the preparation technology and application of vanadium oxide materials. • V 2 O 5 films were deposited on sapphire substrates by radio frequency (R.F.) magnetron sputtering; • Effect of the different oxygen proportion during annealing on thermal transition behaviors was investigated in detail by temperature-dependent Raman and FTIR; • The annealed V 2 O 5 films were transformed into V 2 O 5 , VO 2 (B), and VO 2 (M) by different thermal transition behaviors; • VO 2 (M) films with excellent thermochromic properties can be obtained by controlling the annealing atmosphere and temperature. [ABSTRACT FROM AUTHOR]

Automatic inspection of micro-defects of thin film transistor-liquid crystal display (TFT-LCD) panels is a critical task in LCD manufacturing. To meet the practical demand of online inspection of a one-dimensional (1D) line image captured by the line scan visual system, we propose a robust 1D Fourier reconstruction method with the capability of automatic determination of the period Δx of the periodic pattern of a spatial domain line image and the neighboring length r of the frequency peaks of the corresponding frequency domain line image. Moreover, to alleviate the difficulty in the discrimination between the defects and the non-uniform illumination background, we present an effective way to correct the non-uniform background using robust locally weighted smoothing combined with polynomial curve fitting. As a proof-of-concept, we built a line scan visual system and tested the captured line images. The results reveal that the proposed method is able to correct the non-uniform illumination background in a proper way that does not cause false alarms in defect inspection but also preserves complete information about the defects in terms of the brightness and darkness as well as the shape, indicating its distinct advantage in defect inspection of TFT-LCD panels. [ABSTRACT FROM AUTHOR]

The effects of annealing ambient on the structural and transport properties of epitaxial La0.7 Ba0.3MnO3 films suffering large compressive strain on LaAlO3 substrates (LBMO/LAO) have been investigated. Independent of oxygen or argon ambient, a high temperature (900 °C) post-annealing process leads to a c-axis contraction, which can be attributed to the oxygen transfer from the in-plane to the out-of-plane direction. Meanwhile, the transport properties are similar with each other for both the Ar-annealed and O2-annealed films. The comparison of the ambient annealing effects between the highly strained LBMO/LAO films and negligibly strained LBMO films on SrTiO3 substrates indicates that a large in-plane compressive strain favors decreasing oxygen deficiency in the films, especially in the ab-plane. [ABSTRACT FROM AUTHOR]

Flexible energy storage based on ferroelectric capacitors enjoys high power density and rapid respond time, but the polarization fatigue problems limit its long-term reliability. Bi3.15Nd0.85Ti3O12 (BNT) is a lead-free ferroelectric material with fatigue-free properties, which is promising for applications in long-term ferroelectric devices. Nevertheless, the applications of BNT thin films for energy storage are restricted by their poor energy efficiency and low energy density. In this work, flexible BNT thin films with different numbers of SrTiO3 (STO) insert layers are fabricated on flexible mica substrates by an exquisitely designed dual-target pulsed laser deposition process, and the energy storage performances are effectively optimized via interface engineering. By inserting periodic STO dielectric layers with repetition periods of 100, the energy storage density (Wrec) and efficiency (η) are improved to ∼24.26 J cm−3 and ∼71.93%, which are, respectively, increased to 287% and 132% compared with the pure phase BNT thin film. Importantly, the improved Wrec and η can be well maintained under large bending deformation (bending radius as small as r = 4 mm) and within a wide temperature range (25–175 °C), suggesting its good stability and reliability. These results show that the involvement of periodic dielectric layers in BNT thin films can significantly enhance energy storage density and efficiency and effectively promote its applications in future flexible energy storage devices. [ABSTRACT FROM AUTHOR]

[Display omitted] Gas hydrates have gained great interest in the energy and environmental field as a medium for gas storage and transport, gas separation, and carbon dioxide sequestration. The presence of small doses of surfactants in the aqueous phase has been reported to enhance hydrate formation; however, the underlying mechanisms remain poorly understood. Thus, in situ high-resolution X-ray computed tomography measurements were performed to monitor the upward water migration and the resulting hydrate nucleation and growth. It was found that the presence of hydrate crystals at the gas–liquid–solid contact line triggered the enhanced growth of hydrates on the reactor wall. A time delay was observed between the disappearance of the bulk water reservoir and its transformation into hydrate. The lower interfacial tension between the hydrate surface and the solution facilitated its adsorption onto the reactor wall once a thin film of hydrate nucleated on the solid wall surface. These hydrate layers present on the reactor wall were found to be porous, wherein the porosity decreased with increased subcooling. These fundamental results will be of value in understanding the mechanism of hydrate growth in the presence of surfactants and its potential application in hydrate-based technologies. [ABSTRACT FROM AUTHOR]

An infrared transparent conductive material is a solution to realize the shielding function of infrared windows against electromagnetic waves, by combining the two characteristics of high transmission and conductivity in infrared wavelengths. Indium-hydroxide-doped (In2O3:H) thin films were prepared by atomic layer deposition method, which can achieve high IR transmission by reducing the carrier concentration on the basis of ensuring the electrical properties. On this basis, the effect of the post-deposition annealing process on the microstructure evolution and optoelectronic properties of In2O3:H thin films was investigated in this paper. It is demonstrated that the carrier mobility after annealing is up to 90 cm2/(V·s), and the transmittance at the 4 μm is about 70%, meanwhile, the carrier concentration after annealing in air atmosphere is reduced to 1019 cm−3, with a transmission rate of up to 83% at 4 μm. The simulations visualize the shielding performance of the annealed In2O3:H thin film against radar electromagnetic waves. It provides a guideline for fabricating lightweight, thin, and multi-functional shielding infrared transparent materials in the key fields of spacecraft and high precision electronics. [ABSTRACT FROM AUTHOR]

• A nanostructure was fabricated on the surface of Ti-Cu alloy. • The nanostructure was composed of TiO 2 , CuO and Cu 2 O. • The surface modified Ti-Cu alloy reduced inflammatory response. Once a biomaterial is implanted, inflammatory response will happen on the implant. Prolonged inflammatory events will decrease the implant success rate. Implants with nanostructured surfaces have been considered as an effective strategy to reduce inflammatory response. A TiO 2 nanostructured surface doped with CuO and Cu 2 O on Ti-Cu alloy was fabricated by NaOH, deionized water and heat treatments. The RAW 264.7 macrophages were used to research the inflammatory on the nanostructured surface. The nanostructure presented excellent cytocompatibility, but reduced inflammatory response by downregulating mRNA expressions of proinflammatory cytokines and secretion of proinflammatory cytokine, implying that the nanostructure might benefit implantation success. [ABSTRACT FROM AUTHOR]

In this paper, the single-doped (Ni-WO 3 and Ti-WO 3) and binary-doped (Ni-Ag-WO 3 and Ti-Ag-WO 3) amorphous WO 3 thin films were respectively prepared on indium-doped tin oxide conductive glass substrates by radio-frequency magnetron sputtering. Among the single-doped WO 3 thin films, the electrochromic (EC) properties of films can be enhanced by the presence of Ni or Ti. However, the low conductivity of WO 3 limits its application in EC devices. A novel approach was proposed to ameliorate this disadvantage which has not been explored, that is, the highly conductive Ag was introduced into WO 3 films with Ni or Ti. The experimental results show that the addition of Ag reduces the charge transfer resistance and shortens the ion diffusion path length, thereby improving the EC response time (Ni-Ag-WO 3 : t b =1.16 s; Ti-Ag-WO 3 : t c =4.14 s), electrochemical active area, and ion diffusion coefficients (Ni-Ag-WO 3 : D a =3.032 × 10−9 cm2/s; Ti-Ag-WO 3 : D c =7.737 × 10−9 cm2/s). Based on these work, the feasibility of Ni-Ag and Ti-Ag binary-doped WO 3 films was confirmed. These discoveries contribute to the exploration of preparing high-performance WO 3 EC films for the practical applications of EC devices such as in automatic anti-glare rearview mirrors. [ABSTRACT FROM AUTHOR]

Tensile-strained epitaxial La 0.67Ba 0.33MnO 3 (LBMO) film has been prepared by magnetron sputtering technique on (001) oriented spinel MgAl 2O 4 substrate. The transport and magnetic measurements give an insulator-metal transition and paramagnetic-ferromagnetic transition occurring at ∼150 K and 250 K respectively, which implies the phase separation in such a tensile-strained film. By analyzing the angular and temperature dependences of the ferromagnetic resonance (FMR), we determine the magnetocrystalline anisotropy of the film. It is found that the tensile-strained film is dominated by an easy-axis corresponding to the compressive out-of-plane direction, though the magnitudes of anisotropy constants are relatively small and their temperature dependences are some complex. Furthermore, the FMR spectra show additional spin wave resonance (SWR), and the field positions can be indexed to follow a linear dependence on the square of index n. The scaling gives a spin-wave exchange stiffness D of 20.7 meV Å 2 at low temperature, which is less than half of that in strain-free LBMO films, implying that the double exchange interaction is remarkably suppressed in the tensile-strained LBMO films. [ABSTRACT FROM AUTHOR]

Abstract: The magnetic and transport properties of epitaxial La0.7Ba0.3MnO3 films on LaAlO3 substrates have been investigated and compared with those on SrTiO3 substrates. It is found that the ferromagnetic and metallic transition temperature of the highly compressive strained films on LaAlO3 substrates decreases steadily with decreasing film thickness, while it changes little in the lightly strained films on SrTiO3 substrates. The properties of the films on LaAlO3 substrates are more sensitive to a post-annealing procedure. A tendency to phase separation, which induces a difference between the insulator–metal transition temperature T MI and the Curie temperature T C, is observed for the films with a medium oxygen annealing process. We argue that the phase separation is due to both the highly compressive strain and oxygen deficiency in the films. [ABSTRACT FROM AUTHOR]

The performance of atomic layer deposition films is mainly limited by precursor residues, low crystallinity and densities due to low deposition temperatures. Here, we used atomic layer deposition to deposit tin oxide thin films at a relatively low temperature of 250 °C. At this temperature, the change in the valence of Sn due to precursor residue is eliminated by layer-by-layer Ar plasma treatment, and the crystallinity of the films is improved. The effects of Ar plasma treatment power and Ar treatment time on the structural and optoelectronic properties were investigated. It was found that Ar plasma treatment time more significantly affects the surface morphology and the optical and electrical properties of the film. The film is transparent to both visible and near-infrared light over a wide range of wavelengths from 400 nm to at least 5000 nm. The film resistivity can be as low as 1.117 × 10−3 Ω·cm. The film has a relatively low level of residual stress due to the fact that there is no need to improve the crystallinity of the film by conventional high temperature annealing. On the basis of the high transparency and high conductivity of the SnOx films with layer by layer Ar plasma treatment in situ, the films can be applied as electromagnetic shielding windows for photodetectors. Unlabelled Image • The films exhibit excellent crystallinity and conductivity without the need for a high-temperature annealing step. • Ar plasma treatment significantly reduced the proportion of reduced Sn4+. • The plasma treatment time has a more pronounced effect on the SnOx crystallinity than the treatment power. • Designed and prepared an infrared transparent conductive film with excellent electrical properties and optical transmission [ABSTRACT FROM AUTHOR]

Due to the natural working mechanism of triboelectric nanogenerators (TENGs), potential energy stored by elastic materials may not be effectively converted into electric power, post mechanical triggering. Here, we report a practical bionic-jellyfish triboelectric nanogenerator (bjTENG) with polymeric thin film as the triboelectric material, which is shape-adaptive, with a hermetic package and a unique elastic resilience structure, similar to the behavior of a jellyfish. The charge separation in the elastic resilience of this bionic-structure is based on the liquid pressure-induced contact-separation of the triboelectric layers. On the basis of the conjunction of the triboelectrification and the electrostatic induction, a sustainable and enhanced output performance of 143 V, 11.8 mA/m 2 and 22.1 μC/m 2 under a low frequency of 0.75 Hz and at a water depth of 60 cm is produced, which can be used to supply power for dozens of green LEDs or a temperature sensor directly. More significantly, bjTENG is believed to be a priority technology which is attributable to its highly sensitivity, portability, and suitability for continuous detection of water level and fluctuation. Furthermore, a wireless self-powered fluctuation sensor early-warning system, which provides exact and wireless monitoring of fluctuation of a liquid surface, is also successfully developed. [ABSTRACT FROM AUTHOR]

Lead-free barium tin titanate BaTi 0.85 Sn 0.15 O 3 (BTS) ferroelectric thin films have been deposited on Pt/Ti/SiO 2 /Si substrates by pulsed laser deposition. The structure and dielectric properties of thin films deposited at various oxygen pressures are investigated systematically. By optimizing the oxygen pressure during the deposition, the structure and dielectric properties are improved. The thin films grown at 15 Pa have the best crystal quality and the largest grain size, which result in the enhancement of the dielectric properties. The dielectric constant and loss tangent show the similar trend in the entire oxygen pressure range. The influence mechanisms of the oxygen pressure on the structure and dielectric properties are proposed. The BTS thin films deposited at 15 Pa with large figure of merit (FOM) of 81.1, high tunability of 72.1%, moderate dielectric constant of 341, low loss tangent of 0.009 are considered to be appropriate as a field tunable ferroelectric material for electrically tunable devices. [ABSTRACT FROM AUTHOR]

The effects of post-deposition oxygen annealing temperature on the physical, chemical, and optical properties of gallium oxide (Ga 2 O 3) films were systematically studied in this work. First, Ga 2 O 3 films were deposited on Si (100) substrates by atomic layer deposition (ALD) and then annealed at 500–900 ℃, respectively. Several standard surface analysis methods were used to characterize the Ga 2 O 3 films before and after annealing. X-ray diffraction (XRD) patterns illustrated that the as-deposited amorphous film transitioned to β-phase after annealing at temperatures greater than 600 ℃. Atomic force microscopy (AFM) images showed that the grain size and roughness of the films significantly increased when annealed above 700 ℃. Transmission electron microscopy (TEM) tests presented that the interface microstructure was slightly affected by the annealing process. The effects of the annealing process on optical properties were performed using photoluminescence spectroscopy (PL) and spectroscopic ellipsometry (SE). Moreover, X-ray spectroscopy (XPS) was utilized to extract the oxygen vacancy (V O) concentration, bandgap, and the energy band alignment of Ga 2 O 3. With increasing annealing temperature, it was found that the atomic ratio of O/Ga increased while V O decreased monotonically from 47.4 % to 27.0 %. Density functional theory (DFT) simulation further accounted for energy band shifts resulting from the variation of V O. This study provides a means to achieve high-quality β-Ga 2 O 3 films, highly significant for applications of β-Ga 2 O 3 -based ultraviolet photodetectors and other relevant devices. • The temperature-dependent annealing effect on chemical state, microstructure, and optical properties of Ga 2 O 3 film is systematically studied. • The relationship of the band structure with annealing temperature and oxygen vacancy defects is established. • The energy bandgap of Ga 2 O 3 can be tuned from 4.75 eV to 4.94 eV by controlling the annealing temperature. • The DFT theoretical calculation combined with XPS results gives insight into the effect of oxygen vacancy defects on the properties of the Ga 2 O 3. [ABSTRACT FROM AUTHOR]

Atom passivation with halogen shows the best performance for PbS CQDs optoelectronic application for its short distance and stability via preventing oxidized to CQDs surface. Chlorine is hardly researched for its high activity and low binding energy to Pb. Here, lead halide was used as precursor by surface ligand engineering, introducing halogen during synthesis before ligand exchange and film deposition. Halogen of precursor was proved on the surface of as synthesized CQDs and still passivated on the surface after phase transfer ligand exchange by PbI 2. Mixed halogen surface passivation layer balance the height and width of tunneling barrier between two adjacent CQDs which improving photo detector current and performance. Our works provide Cl doping passivation method but also elucidate understanding of the impact of photo detection performance via mixed halogen passivation. [ABSTRACT FROM AUTHOR]

Incorporation of thermal responsive nanofillers is a promising strategy to induce thermal responsiveness in thin film nanocomposite (TFN) polyamide NF membranes. In this work, thermal responsive zwitterionic nanocapsules (ZN C s) were embedded in the polyamide (PA) active layers to form thermal responsive water transporting channels for thermal responsive nanofiltration performance. The impact from loading level, diameter, cross-linker ratio, and core/shell ratio of ZN C s on the structure, nanofiltration (NF) performance, and thermal responsive sensitivity of TFN membranes were systematically investigated. It was found that ZN C s with the diameter of 100–110 nm, cross-linker ratio of 50 wt% and core/shell ratio of 3:1, and loading level of 0.01% w/v in aqueous phase had induced the highest permeance change slope of 1.04 L m−2 h−1·bar−1 °C−1 (LMHBC) and flux change slope of 6.24 L m−2·h−1·°C −1(LMHC) for ZN C s-TFN membrane, which was 8.7 times higher than that of the pristine TFC-PA NF membranes. The water flux of such ZN C s-TFN membrane increased from 57 L m−2 h−1 (LMH) to 88 LMH at 0.6 MPa from 25 °C to 30 °C without losing its salt rejection rates. [Display omitted] • High thermal-responsiveness NF membranes were developed by embedding thermal responsive zwitterionic nanocapsules (ZN C s). • Embedding ZN C s could increase water flux without sacrificing salt rejections of NF membranes. • Performance of NF membranes could be tuned by the structure parameters of ZN C s. [ABSTRACT FROM AUTHOR]

Interface engineering has emerged as a fertile and efficacious approach to turn functional properties in the field of film systems. In this work, the interfacial properties of sputtered yttrium oxide films on zinc sulfide substrate (Y 2 O 3 /ZnS) were analyzed by transmission electron microscopy (TEM), X-ray photoelectron spectrum (XPS) depth profile and nano-scratch measurement. An interface layer with the depth of 20 nm between Y 2 O 3 film and ZnS substrate was directly observed by TEM. Under different film growth conditions, although the interfacial features including interfacial width and composition distribution exhibit similar behavior, it is found that higher cohesive strength is obtained under a special substrate bias voltage of −160 V at low substrate temperature. Such an enhanced mechanical property can be understood by the role of physisorbed oxygen in the interfacial region, in which less physisorbed oxygen with van der Waals bonds leads to a strong adhesion. Our results provide a favorable strategy to achieve strong adhesion between oxide and sulfide at low temperature, which are urgent in future micro-electric applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Highly crystalline In 2 O 3 films are grown by pulsed reactive magnetron sputtering. • Substrate heating further improves the film crystallinity and conductivity. • 400 °C is the limit for benefiting to obtain the optimum crystallinity of In 2 O 3 films. • The films deposited at 400 °C yield the lowest resistivity of 1.28 × 10-4 Ω⋅cm. • An average transmittance of greater than 80% are also obtained at 400 °C. A transparent conductive oxide (TCO) should have a combination of high electrical conductivity and optical transmission property to fulfill the challenging demands of industrial applications. So far, doped TCOs have been mostly considered to fulfill the technological challenges. In this study, we demonstrate that indium oxide (In 2 O 3) thin films without intentional doping can be deposited with high crystallinity under specific film growth conditions leading to thin films with high mobility, high electrical conductivity, and high transmittance. In 2 O 3 thin films have been deposited by reactive pulsed direct current magnetron sputtering (pulsed DCMS) from an indium target on substrates in a temperature range from room temperature (RT) to 600 °C. Detailed investigations on In 2 O 3 thin films are performed and the film properties such as crystallinity, microstructure, chemical bonding states, electrical and optical properties are revealed. Enhanced plasma density and ionization degree provided by the employed reactive pulsed DCMS and the intentional substrate heating during the thin film deposition give possibility to deposit highly crystalline thin films which are preferentially oriented in (2 2 2) direction. The substrate heating enhances the crystallinity of the grown films up to a certain optimum temperature: 400 °C. When the substrate temperature is above 400 °C, the carrier concentration and mobility decrease due to the grain refinement effect caused by growth competition of grains in different orientations. The films grown at 400 °C indicate the presence of high oxygen vacancy concentrations, which can directly be associated with a high charge carrier concentration despite the lack of intentional doping. The undoped In 2 O 3 films in this study grown at 400 °C show highly promising and competitive electrical properties such as low resistivity of 1.28 × 10-4 Ω⋅cm and the high carrier mobility of 69 cm2/Vs. The average transmittance of the In 2 O 3 films with the highest conductivity is found to be greater than 80% in the visible to the near-infrared spectral region owing to an enhancement in the carrier mobility and an optical bandgap in the range from 3.61 eV to 3.77 eV. [ABSTRACT FROM AUTHOR]

Molybdenum doped zinc oxide thin films have been prepared by RF magnetron sputtering. The influence of the film thickness (120–500 nm) on the structural, electrical, and optical properties of the films is investigated respectively. X-ray diffraction (XRD) studies reveal that with an increase in the film thickness, the crystallinity of the film improves. The obtained film with thickness of 500 nm exhibits the best electrical properties with the lowest resistivity of around 9.6 × 10 −4 Ω cm. The mobility varied from 7.8 to 14.7 cm 2 V −1 s −1 without reducing the achieved high carrier concentration of ∼4.5 × 10 20 cm −3 . Optical band gaps extracted from transmission spectra shows irregular changes due to the Burstein–Moss shift modulated by many-body effects. [ABSTRACT FROM AUTHOR]

Texture could improve the tribological properties of thin films effectively. The mechanism of surface texture improving tribological performance has been extensively studied. However, the coupling effect of surface texture and interface texture on tribological performances needs to be comprehensively understood. In this work, we fabricated surface/interface textured carbon films. The experimental results proved that the tribological properties of carbon films had a remarkable enhancement after adding surface/interface texture and they were strongly related to the texture parameters. The mechanism of the enhanced performance was discussed based on the promotion of transfer films and the enhancement of film-substrate adhesion strength induced by the surface/interface texture. Finally, a coupling effect of surface/interface texture on the tribological performance was proposed. [Display omitted] • A technique for fabricating controllable surface/interface texture was developed. • Tribological properties were significantly enhanced with optimal texture size. • Coupling effect of surface/interface texture on transfer film and film-substrate adhesion was explored. [ABSTRACT FROM AUTHOR]

Abstract: Nickel incorporated amorphous hydrogenated carbon (Ni/a:C–H) thin films were deposited onto the Si substrates via biased target ion beam sputtering of nickel combined with reactive ion beam deposition of a:C–H using CH4/Ar gas mixture. The effects of Ni doping and target bias voltage on the microstructure and mechanical properties of the as-deposited films were investigated by means of X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, transmission electron microscopy and nanoindentation. It was found that the Ni content in the films gets increased with increasing target bias voltage, and most of the Ni atoms react with C atoms to form NiC x phases in the Ni/a:C–H films. Moreover, the nickel carbide nanoparticles attain crystallinity even at low deposition temperature and get embedded in the cross-linked carbon matrix. It was found that the presence of Ni3C nanoparticles tends to increase the content of sp2 carbon, thus decreasing the hardness of Ni/a:C–H films as compared with that of a:C–H films. Additionally it was found that the nickel incorporated films do not show any adverse effect on the osteoblast cellular adhesion. Overall, these carbidic nanocrystals initiate direct graphitization and intend to change diamond-like to graphite-like carbon structure in Ni/a:C–H films with promising biocompatibility. [ABSTRACT FROM AUTHOR]

• AZO/Ag/AZO multilayer films are prone to failures under thermal oxidation. • Inserting Ni layer can improve the photoelectric stability of AZO/Ag/AZO films. • Film had good transmittance, surface resistance and structure after oxidation at 500 °C. • Ag diffusion was inhibited by Ni layer and photoelectric stability was improved. Dielectric/metal/dielectric-structured transparent conductive films are prone to structural and functional failures under thermal oxidation environment. Herein, a Ni layer was employed to improve the photoelectric stability of AZO/Ag/AZO multilayer films. The AZO/Ni/Ag/AZO film exhibited a transmittance of 75%, surface resistance of ~7 Ω/sq, and stable structure after thermal oxidation treatment at 500 °C. The visible light transmittance, surface resistance, and figure of merit values of the AZO/Ag/AZO and AZO/Ni/Ag/AZO films were determined after high-temperature treatment in ambient air. The diffusion of Ag was effectively inhibited by the Ni layer, and the photoelectric stability of AZO/Ag/AZO films was improved under thermal environment. [ABSTRACT FROM AUTHOR]

The magnetocrystalline anisotropy of La0.67Ba0.33MnO3 (LBMO) epitaxial films suffering large compressive strain on LaAlO3 (LAO) substrates (LBMO/LAO) was investigated by ferromagnetic resonance (FMR) in the temperature range between 2 and 320 K. By mapping out the dependence of the FMR position on the angle between the applied magnetic field and crystallographic axes of the films, a large easy-plane anisotropy has been found in such compressive strained LBMO films, which is in contrast to the general tendency presented in strained manganite films. Furthermore, the excellent epitaxial crystallographic orientation due to the LAO substrates gives rise to an appreciable fourfold symmetry of the in-plane anisotropy with easy-axis along the [110] direction. The results are discussed by taking tolerance factor and giant magnetostriction of Ba-doped manganites into account. [ABSTRACT FROM AUTHOR]

• A self-powered vertical heterojunction photodetector based on n-SnOx/p-diamond was fabricated by RF sputtering. • The device has a peak response at 350 nm and responds to light wavelength in the 250–500 nm range at zero bias. • Analysis of the detection mechanism of the n-SnOx/p-diamond heterojunction photodetector. High-performance self-powered UV-blue photodetector was fabricated based on n-SnO x /p-diamond heterojunction. The SnO x film was deposited on the high temperature and high pressure synthetic boron doped diamond wafer by RF magnetron sputtering. This heterojunction device exhibits a good rectification behavior with a rectification ratio of 3.15 × 104 at ±3 V. At zero bias, the device responds in the wavelength ranging from 250 nm to 500 nm with a peak response at 350 nm. The photoresponse rise time and decay time of the device are both less than 2 s under UV-blue illumination with different wavelengths. These results demonstrate that the n-SnO x /p-diamond heterojunction device has potential applications in the field of UV-blue detection. [ABSTRACT FROM AUTHOR]