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• Synthesis of metal oxide nanosheets using ashless filter paper as virtual substrate. • Thickness of the nanosheets ∼3 nm. • Nanosheets do not need any post processing. • In case of mixed precursors, nanosheets as well as nanoparticles are formed. • In case of single precursor, only nanosheets are formed. We present a novel virtual substrate method for large metal oxide nanosheets synthesis. Ashless filter paper was used as the novel virtual substrate and combustive oxidation was used as the synthesis route. CuO/MgO with different proportion in the final produce were selected as model prototype materials to study synthesis kinetics. Aqueous soluble acetate precursors were utilized, and the products were characterized by powder x-ray diffraction (XRD), Raman spectroscopy, and transmission electron microscopy (TEM). The selection of these prototypes was based on their contrasting crystallographic properties and contrasting physico-chemical properties of the respective acetate precursors. This method yields polycrystalline (grain size tens of nm) nanosheets with a thickness of ∼3 nm, which percolate to form centimeter-long freestanding structures. Our synthesis kinetics model establishes that in case of mixed precursor, the precursor with higher solubility/aqueous affinity gets precedence in attaining sheet morphology. In the case of a single precursor, nanosheets were always formed. The growth kinetics for the metal oxide nanosheets is discussed. [ABSTRACT FROM AUTHOR]

• Crystalline half-Heusler alloys have good thermoelectric properties but are brittle. • Amorphous TiNiSn thin films are shown to be ductile. • They adhere well to different flexible substrates owing to strong interfacial bonds. • Amorphous TiNiSn thin films can thus be used for flexible devices. Thermoelectric devices convert heat to electricity without greenhouse gas emissions and have the potential to serve as energy sources in wearable devices. Ongoing efforts are focused on designing materials that offer both high conversion efficiency and mechanical flexibility. Half-Heusler materials, such as TiNiSn, exhibit promising chemical stability and thermoelectric efficiency, but their inherent brittleness poses challenges for applications in flexible devices. Here, TiNiSn thin films were deposited by DC magnetron sputtering at room temperature to investigate their response to bending for flexible devices applications. Therefore, different substrates were considered: Si, Kapton, silk, and printer paper, whereas Si was used as a reference. The composition and structure of the deposited thin films were analyzed by employing energy-dispersive X-ray spectroscopy and wide-angle X-ray scattering, respectively. The film morphology was examined via scanning electron microscopy. Additionally, density functional theory (DFT) was employed to explore interfaces between the flexible substrates and amorphous TiNiSn and calculate the Cauchy pressure, a key indicator of ductile/brittle behavior. Amorphous TiNiSn thin film exhibits good adhesion to flexible Kapton, silk, and paper substrates. Mechanical loading, namely bending up to 154°, was applied to assess crack formation, revealing only a few cracks at 78° and 154°, thus indicating a certain level of flexibility. DFT data support these findings, showing intermediate adhesion strength between amorphous TiNiSn and monomers from the flexible substrates. The calculated Cauchy pressure of 30 GPa suggests the ductility of TiNiSn in the amorphous state. Therefore, replacing alternative time-consuming synthesis methods, eliminating the demand for high temperatures, and providing a nontoxic and cost-effective material with good adhesion to various substrates are reasons why amorphous TiNiSn thin film emerges as a good candidate for flexible thermoelectric devices. [Display omitted] [ABSTRACT FROM AUTHOR]

• Thin-film gold electrodes on glass are cost-effective and easily modified. • Nanoimprint lithography increase electrode surface area to volume ratio. • ZnO nanorods significantly improve the performance of electrochemical sensors. • Modified electrode has higher sensitivity for cadmium ions detection. This paper uses the nanoimprint lithography (NIL) technique to present the fabrication and characterization of Zinc oxide nanorods (ZnONRs)-modified electrodes. Characterization of the resulting electrode involved X–ray diffraction, Field Emission Scanning Electron Microscope and Transmission electron microscopy. The electrode surface was modified with ZnONRs using the NIL technique to increase the sensitivity of the electrochemical sensor for detecting small quantities of heavy metal ions, which remain a major concern due to their toxicity and environmental harm. Electrochemical measurements and sensing performance evaluations were conducted to analyze the electrochemical properties and sensitivity of the ZnONRs - modified electrodes. The results demonstrated increased sensitivity towards cadmium ions present in aqueous solutions, and the limit of detection is found to be 20.88 ± 0.9 µM. [Display omitted] [ABSTRACT FROM AUTHOR]

• Titanium dioxide (TiO 2) particles are clear with increased temperatures and layers. • The size of TiO 2 particles varies with annealing temperature and spin coat layers. • The device shows great repeatability and response time during electrical analysis. This paper investigates the amperometric stability of a Titanium Dioxide (TiO 2) nanoparticle layer on an interdigitated electrode (IDE) to develop stable electronic devices. The devices were tested with varying numbers of spin-coat layers and annealing temperatures to achieve a TiO 2 nanoparticle layer with high crystallinity. Device fabrication involved coating a TiO 2 solution onto a silicon dioxide (SiO 2) wafer with an IDE photomask. The devices were characterized using a Field-emission Scanning Electron Microscope (FESEM) and X-ray Diffractometer (XRD) to verify the crystallinity of the TiO 2. Current-voltage (I-V) curves and real-time current measurements were also conducted to analyze the electrical properties of the device. FESEM results indicate that increasing the number of spin-coat layers and annealing temperature enhances the clarity of the spherical shape of TiO 2 nanoparticles and produces highly crystalline nanoparticles, as confirmed by XRD analysis. In terms of electrical analysis, the device exhibited a sharp increase in current, maintaining a range of 2.5 nA to 10 nA. This concludes that the TiO 2 device is highly sensitive, with excellent repeatability and response time, making it suitable for practical applications. [ABSTRACT FROM AUTHOR]

• Resonant soft x-ray reflectometry 2D maps are modeled for iron oxide multilayers. • Iron oxidation from top/bottom side can be distinguished by reflectance 2D patterns. • Polymorphic Fe 2 O 3 multilayers can be uniquely identified by interference signatures. In the present paper we discuss applicability of the synchrotron method of resonant x-ray reflectometry to non-destructive depth profiling of multilayer heterostructures with low optical contrast between the sublayers. The two-dimensional mapping approach comprising evaluation and measurement of reflectance as a function of photon energy and grazing angle is shown to provide a convenient way to effectively utilize the enhancement of optical contrast between the sublayers that exists at the absorption edges of chemical elements due to particular spectral shape peculiarities related to oxidation state, crystallographic environment and magnetization. In the present study the evaluation of the resonant X-ray reflectivity maps is performed using a specially developed modeling and fitting software. Estimation of the photon energy / grazing angle combinations at which the reflectance is most sensitive to the minor changes in the physical properties of the sublayers is illustrated by the example of ferroic-on-semiconductor nanoscale heterostructures composed of nanoscale film of metallic iron oxidized from either top or bottom side. The subtle differences in resonant soft x-ray reflectance caused by variation of the oxide film thickness, oxidation state and crystallographic environment are discussed. The presented approach is applicable to a large class of heterostructures composed of sublayers that can be distinguished only by the differences in their near edge X-ray absorption fine structure. [ABSTRACT FROM AUTHOR]

• More impurities reduce conductivity in annealed small crystallite (<33 nm) films. • More impurities raise conductivity in annealed large crystallite (>68 nm) films. • Laser annealing stimulates impurity diffusion more than thermal annealing. • Laser-annealed films lose more effects from impurities than thermal-annealed films. In this paper, the changes in microstructure and conductivity of the films before and after thermal and laser annealing are observed, which corresponds to various combinations of crystallite sizes and impurity densities. The results show that the impurities promote grain boundary migration at larger initial crystallite sizes, which contradicts previous reports. This is because the rate of grain growth is determined by the driving force and resistance to grain growth, the former provided by the energy of grain boundaries and the impurities outside the nanograin boundaries, and the latter by the impurities enriched within the boundaries. Additionally, laser annealing is more effective than thermal annealing in stimulating impurity diffusion, resulting in a reduced influence of impurities on grain growth. [ABSTRACT FROM AUTHOR]

• Proposition of a passivation scheme for front surface of cells: SiO x /AlO x /SiN x stacks. • Optimal passivation effect when the thickness of 2 nm SiO x combine with AlO x /SiN x. • When the thickness exceeds 5 nm, the charge polarity in the films becomes negative. • Conversion efficiency of cells with SiO x /AlO x /SiN x stacks improved by 0.11 % abs.. In this paper, an effective P + emitter passivation scheme was proposed by continuously optimizing the passivation layer on the front surface of N-type tunnel oxide passivated contact (TOPCon) solar cells, that was using SiO x /AlO x /SiN x tri-layer passivation stack. The SiO x /AlO x /SiN x stack combined the benefits of the chemical passivation effect of SiO x and the field-effect passivation of SiO x /AlO x stack, resulting in high-quality passivation for boron-doped emitter. Three different passivation schemes of SiN x , AlO x /SiN x and SiO x /AlO x /SiN x were respectively prepared on the front surface of N-type TOPCon solar cells. It was revealed that the cells with SiO x /AlO x /SiN x stack had a superior conversion efficiency, while the SiO x thickness significantly influenced the surface passivation. Through optimization of SiO x thickness in the SiO x /AlO x /SiN x stack, the optimal deposition period for SiO x was 4 cycles by the plasma-enhanced atomic layer deposition (PEALD) process. The N-type TOPCon solar cells with SiO x /AlO x /SiN x stack on the front surface exhibited the highest performances with a conversion efficiency of 24.88 % when the deposition period of SiO x was 4 cycles. Compared with the baseline processes, the efficiency was increased by 0.11 % abs.. [ABSTRACT FROM AUTHOR]

• A diamond nanowire array prepared through a two-step etching. • The high-density diamond nanowire array possesses stable structural properties. • The nanowire array exhibits a reflectance of 0.68 % in the ultraviolet range. Nanostructured blackbodies have a wide application in the fields of light control, energy harvesting and desalination, benefiting from their efficient absorption and radiation on rays with specific wavelength. However, present blackbody materials often suffer deficiencies in stability and mechanical strength. Diamond is an ideal material for blackbody application owing to its excellent stability and corrosion resistance. In this paper, a high-density nanowire array was fabricated on polycrystalline diamond substrate by two-step etching, including hydrogen/oxygen plasma etching and inductively coupled plasma etching. The diamond nanowires have a length of several micrometers and a diameter of about 52 nm. The reflectance spectra verified that the diamond nanowire array has an ultralow average reflectance of 0.7 % within the 500–2000 nm range, demonstrating a reflection reduction by 2530 % compared to the original polycrystalline diamond. The lowest reflectance of 0.5 % was achieved at a wavelength of 1796 nm. [ABSTRACT FROM AUTHOR]

• Four hard X-ray HfO 2 /Al 2 O 3 multilayers with period less than 4 nm fabricated by ALD. • X-ray (0.154 nm) reflectivity of HfO 2 /Al 2 O 3 multilayer with a 3.44 nm period is 24 %. • Similar surface roughness for multilayers with thickness > 200 nm and substrate. Multilayer is a widely used X-ray optics that can be designed and optimized for specific X-ray application. Atomic layer deposition (ALD) has unique advantage in coating homogeneous ultra-thin film on both flat and curved substrates, which shows great potential in the fabrication of X-ray multilayer with small period. In this paper, hard X-ray HfO 2 /Al 2 O 3 multilayers on Si substrate prepared by ALD were investigated. The X-ray (0.154 nm) reflectivity of HfO 2 /Al 2 O 3 multilayer with 3.44 nm period, 60 bilayers is 24 %. Atomic force microscope results show that surface roughness of HfO 2 /Al 2 O 3 multilayer with total thickness more than 200 nm is slightly larger than that of the substrate. High resolution transmission electron microscope images reveal that amorphous HfO 2 /Al 2 O 3 material pair forms multilayer with sharp interfaces even for 1.69 nm period. Further study indicates that lowering substrate roughness can reduce the deviation between actual and theoretical X-ray reflectivity. These results demonstrate that for multilayer-based hard X-ray optics, ALD-grown HfO 2 /Al 2 O 3 is a promising candidate. [ABSTRACT FROM AUTHOR]

• Anions influence mixed (Zn2++Ni2+) ferrite films properties formed on carbon steel. • Faster formation kinetics of nitrate anions resulted in higher film thickness. • Contact angle values indicated hydrophobic nature of mixed ferrite films. • Carbon steel corrosion resistance improved in presence of acetate and nitrate anions. • The complexing stability of anions with cations influences the ferrite composition. The major concerns in Primary Heat Transport circuits of water cooled nuclear power plants are corrosion of structural materials and radiation field buildup on out-of-core surfaces due to accumulation of activated corrosion products. To address these concerns, hot conditioning and metal ion passivation are employed, which lead to the formation of protective magnetite coating on structural alloys like carbon steel. In this study, investigations were undertaken to modify the magnetite/ferrite films hydrothermally in the presence of zinc (Zn2+) and nickel (Ni2+) ions by using different salts of these ions containing anions such as acetate, nitrate and sulphate. Mixed ferrite coatings containing Zn2+ and Ni2+ ions were developed on carbon steel in lithiated water in presence of these anions at 250 °C by hydrothermal method and subsequently characterized by grazing incidence-X-ray diffraction for phase identification and scanning electron microscopy for surface morphology. The effects of these anions were studied by comparing the corrosion resistance properties of ferrite coated carbon steel specimens. The corrosion properties were studied in lithium hydroxide medium at ambient temperature by electrochemical techniques and the results of the investigation are discussed in this paper. [ABSTRACT FROM AUTHOR]

• Nickel-Iron-Cobalt (NiFeCo) with Tb and/or Dy alloys have high magnetostriction. • NiFeCo can retain some of its soft magnetism even when alloyed with lanthanides. • Thick magnetostrictive films can be deposited using electrodeposition. • Fiber-Bragg-Grating provide reliable magnetostriction measurement of thin films. Magnetostrictive thin films have numerous applications in communications, sensors, and microelectronic devices. Such devices usually require magnetostrictive thin films with large magnetostriction and soft magnetic properties. Nickel-Iron-Cobalt (NiFeCo) alloys have excellent soft magnetic properties and can be easily fabricated as thin films. However, their main drawback for these sensing applications is that they have very low magnetostriction. On the other hand, Iron-Rare Earth (RE) alloys such as Fe-Tb-Dy or Fe-Ga have large magnetostriction at the cost of some soft magnetic properties. Moreover, their magnetostrictive properties are degraded when reduced to thin films as opposed to bulk materials due to structural imperfections and oxidation of the REs. In this paper, we report the development of NiFeCo thin films with incorporated rare earth elements prepared via electrodeposition. Electrochemical cells were prepared using Ni, Fe, and Co sulfate salts. Tb and Dy sulfates were added to the electrochemical cell in order of increasing concentration. Electrodeposition was then carried out under galvanostatic control for each RE concentration in the bath. The produced films were analyzed for composition, crystallinity, and magnetic properties to draw out trends based on the initial concentrations of rare earth salts in the bath. The produced thin films retained soft magnetic properties while exhibiting giant magnetostriction of up to ∼370 ppm depending on the type and amount of incorporated REs within the film. The combination of soft magnetism and giant magnetostriction makes these NiFeCo thin films with added Tb and Dy excellent candidates for developing resonant frequency sensing devices. [ABSTRACT FROM AUTHOR]

• Hf 6 Ta 2 O 17 films with accurate component segregation are prepared by sol-gel method. • Component segregations could strengthen Hf 6 Ta 2 O 17 polycrystalline films. • Ta 2 O 5 Hf 6 Ta 2 O 17 eutectic system could resist elastic deformation. • Grain boundaries induced by excessive HfO 2 will accelerate dissipation of energy. With outstanding thermal and mechanical properties, Hf 6 Ta 2 O 17 emerges as an ideal candidate for next-generation thermal barrier coatings (TBC) material. However, high-temperature process during TBC fabrication will inevitably lead to Ta 2 O 5 /HfO 2 component segregation because large differences in vapor pressure. In this paper, Hf 6 Ta 2 O 17 polycrystalline film with different Ta 2 O 5 /HfO 2 component was prepared on sapphire substrate by sol-gel method through spin coating. Morphological analysis indicates the excessive Ta 2 O 5 can reduce the porosity in Hf 6 Ta 2 O 17 thin film through eutectic process, while excessive HfO 2 will lead to a worse morphology and smaller average grain size. Nanoindentation reveals that component segregation of excessive Ta 2 O 5 /HfO 2 could both be used to strengthen of Hf 6 Ta 2 O 17 through different mechanisms. In addition, a higher elastic recovery rate in excessive Ta 2 O 5 system indicates Ta 2 O 5 Hf 6 Ta 2 O 17 eutectic system could accelerate energy dissipation and further enhance the toughness for Hf 6 Ta 2 O 17. This work provides a deep insight into the strengthening mechanism of ceramics Hf 6 Ta 2 O 17 with component segregation and paves the way to design of next-generation TBCs. [ABSTRACT FROM AUTHOR]

• SiOC thin films were deposited by remote plasma chemical vapor deposition. • The carbon content could be controlled within the range of 43–3 % with k of early 3.0 s. • Despite of O 2 plasma treatment, Si C bond structure maintained well. • With in situ O 2 plasma treatment, it was possible to improve densities. • At the same time, it was possible to improve electrical and etch properties. In this paper, a study was conducted on silicon oxycarbide thin-film deposition using remote plasma chemical vapor deposition. A di-methyldimethoxysilane) 2 styrene (MDMS) 2 styrene precursor and CH 4 plasma were used in the deposition process, and in situ oxygen plasma treatment was performed to control the carbon content and properties of the thin film. During the deposition process, the thin-film growth rate was found to be almost constant regardless of in situ plasma treatment. This means that in situ oxygen plasma treatment had no significant effect on thin-film growth itself. Auger electron spectroscopy analysis revealed that the carbon content of the deposited thin film was 43 % when only deposition was performed, but could be lowered to 3 % by in situ oxygen plasma treatment, which demonstrated that the carbon content can be controlled in a relatively wide range. X-ray photoelectron spectroscopy showed that it was possible to preserve Si C bonds even as the oxygen content increased with the number of in situ plasma treatments. The refractive index increased from 1.33 to 1.49, indicating a decrease in the number of pores and an increase in density. Meanwhile, the dielectric constant increased with the oxygen content, but did not exceed 3.9 due to the Si C bond structure. As the pore size decreased, the leakage current tended to decrease to 9.51 × 10−9 A/cm2 in an electric field of 1 MV/cm, and the breakdown voltage increased. Finally, it was possible to improve the etching characteristic through plasma treatment by lowering the wet etch rate from 78 to 19 Å/min. [ABSTRACT FROM AUTHOR]

• Aluminum silicon (AlSi) and aluminum (Al) films are subject to fatigue test. • Adding silicon (Si) increases mechanical characteristics in Al film. • Fatigue crack propagation in AlSi film is 10 times slower than that in pure Al film. • AlSi film's fatigue crack propagates in a zigzag way while detouring Si segregation. This paper focuses on investigating the differences in fatigue fracture between sputtered aluminum silicon (AlSi) alloy and pure aluminum (Al) films by means of pulsating-tension cyclic loading tests. AlSi alloy film with 1.0 wt% (wt%) silicon (Si) and pure Al film are prepared at a substrate temperature of 450 ℃ and 260 ℃, respectively, by dc magnetron sputtering. After annealing those films at 490 ℃ under a hydrogen and nitrogen atmosphere for 1 hour, the tensile test specimens are prepared using semiconductor fabrication technologies. Quasi-static tensile tests measure the mean yield strength of 52 MPa and 33 MPa for AlSi and Al films, respectively, which are used as reference stress values for fatigue tests. During fatigue tests, a crack is introduced at the one-side edge of pure Al film specimen and propagates straightly to the other side, whereas a zig-zag crack is observed in AlSi alloy film. The crack propagation rate for AlSi film is around one-tenth of that for pure Al film. The mechanism of fatigue crack propagation is discussed based on element mapping results by energy dispersive X-ray analysis. [ABSTRACT FROM AUTHOR]

• Simple, robust and low-cost method to fabricate thermal responsive coatings on glass. • The coatings show a reversible clear-opaque switching behavior. • The coatings were stable for more than 6 months at room temperature. This paper introduces a simple, robust and inexpensive method to create a thermal responsive coating for glass. The coating is a copolymer of N‑isopropylacrylamide (NIPAAm) and acrylamide (AAm), which can switch between clear and opaque states reversibly. The switching temperature can be adjusted from 32°C to 40°C by varying the percentage of acrylamide. The coating remains stable after switching 30 times and possesses switching function after six months storage at room temperature. These advanced properties enable the smart coating to be suitable for privacy and solar adaptive control. [ABSTRACT FROM AUTHOR]

• HfO 2 and Dy-doped HfO 2 thin films and memories prepared by spin-coating. • Adding Dy ions induces a phase transition from monoclinic to cubic HfO 2. • Dy ions cause structural defects in HfO 2 , affecting optical properties. • Incorporating Dy concentration was observed to improve resistive bipolar behaviour. • 10 wt% Dy film presented space-charge-limited-conduction in the high resistive state. This paper studies the effect of Dy on the structure, morphology, and optical properties of HfO 2 thin films deposited on fused silica substrates and the optical transparency and resistive switching (RS) behavior of the thin films as an active insulator layer in Ag/active insulator layer/ITO/glass memories. Thin films were deposited by spin-coating using a precursor solution obtained by the Pechini-type sol-gel method. The structural analysis revealed that the insertion of Dy ions into the HfO 2 lattice caused the phase transformation from the monoclinic to the cubic phase. Morphological analysis revealed that the thin films had thicknesses between 98 and 101 nm, and their surfaces were composed of 3D islands formed by aggregates of spherical particles ranging from 8 to 5 nm. The active insulator layers had thicknesses ranging from 235 to 218 nm, with no cavities or cracks between them. The optical transparency of the active insulator layer/ITO/glass memory structures was between 70 and 87 %. Optical transmittance, optical bandgap, and optical constants were modified incorporating Dy ions into HfO 2 thin films compared to the undoped HfO 2 thin films. Incorporating Dy ions into HfO 2 increased oxygen vacancies in the active insulator layers. The memory with 10 w% of Dy had the highest resistance off/on ratio of 9.04 compared with undoped HfO 2 memory. Also, the conduction mechanism in the high resistive state (HRS) of the memory with 10 w% of Dy was related to ohmic conduction and space charge limited conduction (SCLC). [ABSTRACT FROM AUTHOR]

• Polycrystalline CdTe is the most successful thin film photovoltaic technology. • High efficiency solar cells are achieved through recrystallisation of the absorber. • Randomization of the absorber texture correlates with increased cell efficiency. • Texture randomization is quantified using 'multiples of uniform density' or MUD values. A range of microstructural changes occur during the deposition and activation of CdTe based thin film solar cells. In particular, the cadmium chloride (CdCl 2) activation treatment results in wholesale recrystallisation which transforms the conversion efficiency of the solar cell. One of the noticeable effects is the change of preferred orientation of the CdTe absorber. Highly orientated [111] texture is observed in as deposited or under-treated CdTe based devices. Optimized activation results in a more randomized texture and the [111] preferred texture component is significantly weakened. In this paper we use Electron Backscatter Diffraction to characterise absorber cross-sections. The focus is on how randomization of the absorber texture reflects device performance. We have had access to a range of CdTe devices using a variety of deposition techniques. We have observed a clear pattern that shows that devices with a highly orientated [111] texture have poor efficiency. Devices with a randomized texture have much higher efficiency. Here we illustrate this empirical correlation using devices deposited by Metal Organic Chemical Vapour Deposition with a range of efficiencies from 13.1 % to 17 %. We have also included the analysis of an absorber from a 18.7 % high efficiency CdSeTe/CdTe device to show that texture is similarly important in these advanced devices. We have been able to quantify the effect of texture by using multiples of uniform density or (MUD) values from the inverse pole figures. MUD figures close to 1 correlate with highest efficiency. Although the random texture of the absorber microstructure is only one of several important process factors, it appears to be a necessary feature for highest efficiency CdTe-based polycrystalline solar cells. [ABSTRACT FROM AUTHOR]

• A mechanism is proposed to explain the as-deposited morphology of the film. • The shelf time has a strong impact on the phases present in the precursor. • Annealing above 310 °C erases the sample's history and yields consistent phases. • Between 310 °C and 520 °C, only Cu 9 (Ga,In) 4 and Cu 16 (Ga,In) 9 found in Cu-In-Ga. • The implications for high quality CuInGaSe 2 manufacturing are discussed. We study by in-situ X-ray diffraction (XRD) in a unique, custom-made furnace mimicking an industrial setup, the effect of pre-annealing on electroplated and sputtered thin films of Cu-In-Ga, as precursor material for Cu(In,Ga)(S,Se) 2 (CIGS)-based solar cells. In the first part of the paper, the properties of the as-deposited precursors are investigated. We propose a mechanism to explain how indium, despite being deposited before gallium, systematically ends up on top of the stack. The shelf time at room temperature is also shown to strongly affect the metallic phases present in the precursor, unlike sputtered precursors where only minor changes can be observed. These results are then used as input for the second part of the paper. In the second part, pre-annealing experiments up to 550 °C are carried out on the electroplated and sputtered precursors at atmospheric pressure in an inert N 2 atmosphere and analysed by in-situ XRD. We find that above the decomposition temperature of Cu 11 In 9 (310 °C) and below around 520 °C, mainly Cu 9 (In,Ga) 4 is left in all precursors, regardless of the phases initially present at room temperature or whether the samples were electroplated or sputtered. We validate these findings for a fast heating ramp to 350 °C, followed by a dwell, as is commonly applied in many CIGS fabrication processes. The implications of these results to high quality CIGS manufacturing are then discussed. [ABSTRACT FROM AUTHOR]

• Thin films deposited by pulsed laser deposition technique on MgO substrates. • Thickness of deposited thin films is approximately 100 nm. • Surface roughness of thin films ranges in between 0.34 nm to 0.62 nm. • Cobalt shows +2 oxidation state while iron shows +2 and +3 oxidation states. • Curie temperature is higher than 400 K. The thin film samples of pristine and Ni-doped Cobalt ferrite(CFO) are deposited on MgO(110) substrates through pulsed laser deposition technique. The recorded X-ray diffraction scans of the samples confirms the thin film deposition of the said material on the given substrate. From the Atomic Force Microscopy studies, the surface roughness of CoFe 1.7 Ni 0.3 O 4 thin film is found to be 0.62 nm, which is more than CoFe 2 O 4 and CoFe 1.5 Ni 0.5 O 4 (0.34 nm and 0.45 nm), attributed to the surface defects and recrystallization process. The x-ray photoelectron emission spectroscopy (XPS) survey spectra of the thin film samples confirm the presence of Co, Ni, Fe, O and C. In our case, the XPS-wide scans revealed the +2-oxidation state for Co and +2 as well as +3 oxidation states for Fe. The respective binding energy positions and the ratio of relative contribution to the overall intensity of Co and Fe ions at the octahedral and tetrahedral sites are also discussed in this paper. It has been shown that the Field Cooled-Zero Field Cooled magnetization curves do not merge until 400 K, which confirms that the Curie temperature T c is higher than 400 K. [ABSTRACT FROM AUTHOR]

• Chemical bath-deposited CdS films show an optical energy band gap of 2.42 eV. • The CdS films show optical transmission of 75 % in the 500–900 nm wavelength range. • We have studied the wavelength dependence of photoconductivity of these CdS films. • Photoconductivity peaks at 492 nm showing an electrical energy band gap of 2.52 eV. • Annealed CdS films show improved conductivity, carrier concentration, and mobility. This paper presents a comprehensive study of the optical transmission, photoconductivity, and morphology of CdS thin films deposited via the chemical bath deposition (CBD) method. The films deposited for 60 min exhibit an optical energy band gap value of 2.42 eV and the highest optical transmission of 75 % in the wavelength range of 500–900 nm. For these films, the transmission electron microscopy imaging shows a distribution of particle sizes around 10 nm. The wavelength dependence of the photoconductivity, extracted from photo resistivity data, shows that the maximum photoconductivity occurs at 492 nm wavelength. This corresponds to an electrical energy band gap of 2.52 eV, which is greater than the optically measured energy gap of 2.42 eV. Based on these results, the electron-hole pair binding energy for CdS films is estimated as 100 meV. According to the electrical resistivity vs. temperature measurements, the activation energy is 1.26 eV which agrees with the electrical energy band gap of 2.52 eV. CdS films annealed under nitrogen gas at 200 °C for one hour exhibited an energy gap of 2.32 eV. These films displayed a conductivity of 60 × 10−4 Scm−1, a carrier concentration of 6.38 × 1014 cm−3, and a mobility of 7.46 cm2 V−1 s−1. These impressive characteristics suggest the suitability of CBD-grown CdS films annealed at 200 °C in nitrogen gas, to be used as the window material in CdS/CdTe thin film solar cells and other optoelectronic applications. [ABSTRACT FROM AUTHOR]

• c/a ratio of Pb 0·92 (La 1-y Eu y) 0·08 (Zr 0·52 Ti 0·48)O 3 (PLZT) film rises with Eu doping. • The d 33 value of PLZT film improves with Eu doping (y = 0.5). • The Young's constant of PLZT film lowers with Eu doping (y = 0.5). • Frequency stability of the PLZT film improves up to 1 MHz with Eu doping (y = 0.5). This paper investigates the effect of europium (Eu3+) doping on the crystal structure, dielectric and piezoelectric properties of lead lanthanum zirconate titanate (PLZT) thin film. For the present study, Pb 0·92 (La 1-y Eu y) 0·08 (Zr 0·52 Ti 0·48)O 3 (PLEZT) compositions with various Eu concentrations (y = 0.0, 0.3, 0.5 and 0.7) were prepared on Si/SiO 2 /Ti/Pt substrates by chemical solution deposition technique. The X-ray diffraction and Raman spectroscopy studies revealed the structural distortions in PLZT films with Eu doping. The piezoelectric charge coefficient showed significant enhancement with Eu doping for y = 0.5 composition, with good room temperature frequency stability. This improvement in the piezoelectric characteristics of PLEZT films is the result of stronger intrinsic contributions brought in by bigger c/a ratios and higher extrinsic contributions from non-180° domain wall motions. [ABSTRACT FROM AUTHOR]

• Plasma treatment of solar cell for 1 min increased power conversion efficiency. • Plasma treatment reduces the defect densities in the heterojunction. • Reduction in the recombination processes due to plasma treatment. • Improves the SiNWs properties that improves the efficiency of the solar cell. Silicon Nanowires (SiNWs) can be easily synthesized by following the two-step electroless metal-assisted chemical etching method. These SiNWs are well known for their low reflectivity due to their excellent light-harvesting characteristics. In this paper, we demonstrated the effect of plasma treatment time on the performance of SiNWs solar cells. The 1 min plasma-treated SiNWs/Poly 3,4-[ethylene dioxy thiophene:Polystyrene sulfonate] (PEDOT׃PSS) solar cell showed increased power conversion efficiency than the untreated SiNWs/PEDOT׃PSS solar cell. The photo Current density-Voltage (J-V) analysis showed that the open circuit voltage (V O C) of the plasma treated solar cell for 1 min is higher (270 mV) than that of the untreated solar cell (120 mV). The increase in the value of V O C comes from different factors׃ one is due to the formation of a good interface between the SiNWs and PEDOT׃PSS layer; other is the reduction of defect densities in SiNWs/PEDOT׃PSS heterojunction, consequently the reduction in the recombination processes. Hence from this research, we found that by controlling the plasma treatment on SiNWs, it can improve the SiNWs properties which can further improve the efficiency of the solar cell. [ABSTRACT FROM AUTHOR]

• G-MWCNTs/TiO 2 hybrid coated surfaces showed super hydrophilic properties. • 0.2 and 0.3 wt.% G-MWCNTs improved the optical transmission in the visible region. • According to the ISO 10,678:2010, hybrid coated samples showed photonic efficiency. This paper presents the findings of the structure, wettability and photocatalytic activity of 32 wt % graphene-doped multi-walled carbon nanotubes (G-MWCNTs) / titanium dioxide (TiO 2) hybrid coatings under three different ratios. The hybrid coatings of G-MWCNTs/TiO 2 were compared with the pure (undoped) TiO 2 coating. Pure TiO 2 and G-MWCNTs/TiO 2 hybrid coatings were prepared by sol-gel method and deposited on soda-lime-silica (SLS) glass substrates using a dip coater. The samples were heat-treated in the air at 500 °C for 1 h. The nano-sized G and MWCNTs used as dopants in the resulting hybrid solution were mixed without agglomeration by the sonication method based on the DLVO theory, without any surfactants. To prevent the migration of Na+ ions contained in the structure of SLS glass to TiO 2 -based coatings, a SiO 2 -based sol-gel coating was first deposited on the SLS glass surface using the dip coating method. This was done before applying the pure TiO 2 coating and G-MWCNTs/TiO 2 hybrid coating process. All samples were crystallized in the anatase form and exhibited superhydrophilic behavior. The G-MWCNTs/TiO 2 hybrid coated samples' photoactivity was determined using the ISO 10678 MB degradation standard. According to the ISO 10678:2010 MB degradation standard, G-MWCNTs/TiO 2 hybrid coated samples exhibited photonic efficiency. [ABSTRACT FROM AUTHOR]

• Modified polymer poly (3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS). • Potassium chloride (KCl) doping improves the charge transfer ability of PEDOT:PSS. • KCl optimizes the energy level mismatch between PEDOT:PSS and perovskite layers. • KCl doping downshifts the energy level of PEDOT:PSS ∼ 0.22 eV. Tin-based perovskite solar cells (PSCs) have been the focus of substantial research globally as a promising choice for lead-free PSCs. Sn-based PSCs performance, however, the performance of PSCs is still significantly inferior to that of lead-based PSCs. The disparity between the energy band levels of the perovskite absorber and charge transport layers, as well as the chemical instability of Sn halide perovskite crystals, are the primary constraints in this regard. Herein, potassium chloride (KCl) was added to polymer poly (3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) to improve the ability to transport holes and match energy levels. The formamidinium tin triiodide based PSCs constructed on KCl-doped PEDOT:PSS has a 5.9 % power conversion efficacy with a low hysteresis, which is comparatively higher than of the control devices (4.3 %). The improvement in photovoltaic performance has been predominantly attributed to two effects, specifically; PEDOT: PSS conductivity and hole extraction, both of which improved following KCl doping. More intriguingly, the modified device exhibit increased open-circuit voltage due to the downshift of PEDOT:PSS energy level by KCl doping. The composite hole transport layer strategy described in this paper provides a means for energy level adjustment and charge transport to enhance the performance of Sn-based PSCs. [ABSTRACT FROM AUTHOR]

• Direct pull-off tests on thin films and comparison with scratch-induced delamination. • Quantify thin films' adhesive strength within 5.5 % to 8.4 % standard deviation. • Scratch-induced delamination is consistent with tensile adhesive failure. • Interfacial adhesive strength is independent of thin films' thickness. • Adhesion energy and fracture resistance can be derived from scratch analysis. The performance and reliability of integrated circuits depend on the mechanical and electrical properties of the interfaces between thin films and the silicon wafer. One of the essential properties of the interface is its adhesion energy. However, conventional adhesion characterization methods could be further improved, especially in providing repeatable and reliable measurements. In this paper, we measured the adhesive strength of the interface between tungsten thin films and silicon wafers in micro-sized specimens using a direct push-to-pull device built into a nano-indenter. A scratch method with a transparent theoretical model was applied to quantify the same interfaces' adhesive strength, adhesion energy, and fracture resistance. Microscopic and mechanical analysis clarified the physical origin of thin film delamination. The current method precisely quantified the interfaces' adhesive strength and fracture resistance. This method is promising for sub-micron thin film designs in the semiconductor industry with its superior repeatability, reliability, and ease of operation. [ABSTRACT FROM AUTHOR]

• Investigation of tunnel oxide passivated contact (TOPCon) for bifacial solar cells. • Thin n-TOPCon deteriorated and thick p-TOPCon improved after firing. • Double-side TOPCon precursors showed improvement after firing. • The roughened p-TOPCon achieves lower contact resistivity compared to planar. • Simulated 22.5 % double-side TOPCon solar cell with a potential of >24 %. This paper presents detailed characterization and analyses of the optical, electrical, and contact properties of a 35 nm phosphorus-doped (n-type) polysilicon (poly-Si) and a 250 nm boron-doped (p-type) poly-Si deposited respectively on textured and roughed surface. These layers could be applied respectively to the front and rear sides of an n-type Si to produce back junction bifacial screen-printed double-side tunnel oxide passivated contacts (DS-TOPCon) solar cells. Optical and device modeling revealed a short circuit current density loss of 1.5 mA/cm2 and 0.5 mA/cm2 due to absorption in the front n-TOPCon and rear side p-TOPCon layers, respectively. The passivation and contact properties including metalized and unmetallized recombination current density (J 0), as well as contact resistivity, were determined as a function of contact firing temperature in the range of 700∼800℃. The passivation quality of the front thin n-TOPCon was found to deteriorate with increased firing temperature while the rear thick p-TOPCon improved. The study showed that the simulated contact firing at 730℃ resulted in the best unmetallized double-side TOPCon precursor, with an excellent implied open-circuit voltage of 730 mV and implied fill factor of ∼86 %. However, the metalized J 0 increased and contact resistivity decreased monotonically with the increase in the firing temperature. The 2D device simulations revealed that these layers can produce screen-printed DS-TOPCon cells with an efficiency of ∼22.5 %. Solar cell modeling also showed that the DS-TOPCon solar cell efficiency can reach 24.1 % by decreasing the n-TOPCon thickness to 20 nm and lowering the full area metalized J 0 to ∼100 mA/cm2. [ABSTRACT FROM AUTHOR]

• Higher growth temperature significantly changes the grain size of AlN thin films. • Crystallinity is obviously improved when the growth temperature exceeds 900 ℃. • Using higher reactor pressure slows down the film deposition rate. • The effect of reactor pressure on growth rate is stronger at low pressures. Following the development of the semiconductor industry, advanced and multifunctional material aluminum nitride (AlN) is widely used. However, AlN thin film faces the dilemma of low crystal quality or cracking in practical applications. This paper presents a high crystal quality and crack-free AlN thin film with a thickness of over 510 nm grown on a sapphire substrate by metal-organic chemical vapor deposition (MOCVD). We have analyzed the thin film deposition mechanism of the MOCVD reaction system using different growth temperatures and reactor pressures and optimized the growth mode of AlN thin film. Wherein the growth temperature refers to the substrate temperature while the film is deposited. It was shown that the deposition rate of the AlN thin film is significantly affected by the reactor pressure. As shown by the x-ray diffraction patterns, the AlN thin films exhibit a (002) preferred orientation while non-(002) reflections are extremely weak. At constant pressure, the intensity of the diffraction peak of (002) orientation increased with the growth temperature. Furthermore, the surface morphology observed by atomic force microscopy revealed a decrease in the surface roughness with increasing growth temperature. The AlN thin film grown at a growth temperature of 1300 ℃ under 10,000 Pa exhibited better (002) orientation in this work. The full width at half maximum of its rocking curve was 0.033° for (002) planes. Beside, the sample showed a flat and dense surface with a root-mean-square surface roughness of 8.4 nm. This study offers an improvement in the deposition of AlN thin films, promising for AlN-based devices operated in various conditions. [ABSTRACT FROM AUTHOR]

• Understanding of early stage of oxidation of Crofer steel by in-situ high temperature X-ray diffraction. • Grazing-incidence X-ray diffraction shows the formation of Cr 2 O 3 and MnCr 2 O 4 spinel. • Glow discharge optical emission spectroscopy depth profiles revealed two-layer oxidation mechanisms. • Top, discontinuous MnCr 2 O 4 spinel and subscale Cr 2 O 3 layer result from the oxidation. Crofer 22 APU is used as metallic interconnects in stacking solid oxide fuel cells (SOFCs) operated at elevated temperatures (above 700 °C) owing to their excellent oxidation resistance. Understanding the protective layer formation in the initial oxidation stage would be useful for optimizing and designing protective coatings for extended life. Initial stage oxidation of Crofer 22 APU steel using surface analytical tools such as glow discharge optical emission spectroscopy (GD-OES), grazing incidence X-ray diffraction (GIXRD), Raman spectroscopy, and atomic force microscopy (AFM) are studied in the paper. An oxidation test on as-received Crofer 22 APU steel was carried out in a controlled atmosphere (0.01 Pa) in an in-situ high-temperature X-ray diffraction (XRD) stage at 950 °C. Normal XRD showed no indication of oxidation, while GIXRD revealed the formation of two-layer oxides: Top layer spinel MnCr 2 O 4 and fine-grained inner layer Cr 2 O 3 , which was confirmed and quantified by GD-OES depth profiling. The Cr 2 O 3 formed initially led to the formation of MnCr 2 O 4 spinel during the initial stage. The rapid diffusion of Mn through the fine-grained Cr 2 O 3 layer results in an increased growth rate of MnCr 2 O 4 spinel on the top of the fine-grained Cr 2 O 3 layer. [ABSTRACT FROM AUTHOR]

• Electrical properties of CuI thin film were modulated by trimethylsilyl iodide treatment. • Trimethylsilyl iodide did not change the optical transmittance and surface morphology of CuI. • Performances of p -CuI/ n -ZnO diodes were enhanced by the trimethylsilyl iodide treatment. This paper reports a facile method to modulate the electrical properties of copper iodide (CuI) thin films, which have attracted considerable attention as a promising transparent conducting p -type semiconductor. Trimethylsilyl iodide (TMSI) was used as an agent for the fast iodination treatment of p -CuI, even at a low processing temperature of 60 °C. A TMSI treatment of less than 30 µL was effective in improving the surface morphology of CuI thin films. The optimal TMSI treatment with 20 µL enhanced the electrical properties of p -CuI by increasing the hole concentration without degrading the optical transmittance. As the TMSI content increased from 0 to 20 µL, the hole concentration of the CuI thin films increased from 4.06 × 1019 to 8.82 × 1019 cm−3. The TMSI treatment eliminated I-vacancies while forming Cu-vacancies that acted as an acceptor dopant. Therefore, the hole concentration in CuI thin films increased with the TMSI treatment. The performance of p -CuI/ n -ZnO diodes, such as on/off ratio, turn-on voltage, and ideality factor, was enhanced by the facile TMSI treatment. [ABSTRACT FROM AUTHOR]

• Kesterite Cu 2 ZnSnS 4 thin film is synthesized by electrodeposition. • Cu-Zn-Sn-S growth revealed progressive nucleation and diffusion-limited growth. • The applied potential does not influence the nucleation. • The CZTS physicochemical properties depend on the electrodeposition time. In this paper, earth-abundant and environmentally friendly kesterite Cu 2 ZnSnS 4 (CZTS) thin films are successfully synthesized by electrodeposition on Indium Tin Oxide (ITO) coated glass for photovoltaic application. For the first time, the electrochemical nucleation and growth mechanisms of the kesterite electrodeposition are investigated. Here, the electrochemical growth mechanism is studied and the diffusion coefficient D is calculated for different applied potentials. Our findings show that kesterite deposition occurs through progressive nucleation followed by the limited growth of diffusion of 3D hemispheric islands. Furthermore, it has been proven that the type of nucleation and growth is not influenced by the applied potential. Scanning electron microscopy, X-ray diffraction and UV–vis are used to characterize the physicochemical properties of the prepared samples. The morphological and crystallographic investigations reveal a different morphology and structure of the CZTS film deposited at different potentials for different times. Among the samples studied, the CZTS thin film prepared at −1.1 V for 60 min offers the best properties with 2.4 µm thickness after annealing at 450 °C. [ABSTRACT FROM AUTHOR]

• Dependence of SiC:H film's physical properties on RF sputtering power was studied. • Presence of nanopores between nanoparticles formed at lower RF power was established. • Most effective AR coating was obtained by deposition of SiC:H film at 150 w RF power. • Maximum passivation effect was achieved at the highest considered RF sputtering power. • Correlation between the structure and physical properties of SiC:H films was shown. In this paper, optical and passivating properties of hydrogenated silicon carbide synthesized by reactive magnetron sputtering for c-Si solar cell application were studied. SiC:H films were synthesized by sputtering a SiC target in an argon-hydrogen ambient at a Radio Frequency (RF) power of 100–250 W. The thickness, density, and roughness of the films were measured by X-ray reflectometry. The optical properties of the films were studied by UV–visible spectroscopy. It is shown that with an increase in RF power, the refractive index increases from 1.53 to 2.32 (at λ = 633 nm), and the extinction coefficient does not exceed 0.009 in most of the visible and near-IR spectrum. Based on the measured optical constants using computer simulation the optimal thicknesses were calculated to maximize antireflection effect. IR spectroscopy showed correlation between the structure and physical properties of the films. It has been established that, at a lower RF power (100–150 W), particles are deposited instead of atoms. This leads to the formation of voids at the particle boundaries, which are subsequently filled with oxygen. Using the non-contact microwave photoconductance decay method, it was shown that the maximum effective lifetime (τ eff) is achieved at RF power of 250 W. In addition, influence of preliminary surface cleaning procedure and post-annealing in vacuum on the τ eff was considered. [ABSTRACT FROM AUTHOR]

• For three HfO x -based structures bipolar resistive switching was demonstrated. • In HfO 2 /HfO x Ny/TiN filaments appeared on defects in the active layer. • Al 2 O 3 layer reduces the cross-sections of conductive filaments. • The Al 2 O 3 /HfO 2 /TaO x Ny/TiN structure has a great potential for memory applications. The paper describes an investigation of resistive switching in the Pt/HfO 2 /HfO x N y /TiN, Pt/HfO 2 /TaO x N y /TiN, and Pt/Al 2 O 3 /HfO 2 /TaO x N y /TiN structures with oxide layers deposited by atomic layer deposition. Using conductive atomic force microscopy, we demonstrate the formation of conductive filaments in every structure. We also perform a complete resistive switching cycle. We define the properties of the filaments formed at different voltages and present the size and conductivity distributions of the filaments. Our research confirms that filaments in amorphous hafnium oxide initiate on the film defects, however, defects at different materials interfaces can enhance filament density in structures with different oxide layers. It appears that among the presented structures, the Pt/Al 2 O 3 /HfO 2 /TaO x N y /TiN structure has the greatest potential for use in resistive random-access memory. [ABSTRACT FROM AUTHOR]

• Multi-layered stable laser induced graphene as wearable heating pad is fabricated. • Excellent heating at 10 v of temperatures up to 195 °C. • Enhanced flexibility and durability for wearable electronics applications. • Washable robust design for tough environments such as socks and gloves. Increasing demand for wearable sensors and heating elements has occurred recently. Herein, graphene has been observed as a biocompatible, cost effective, and multidimensional material catering to both sensing and heating applications. However, it still lacks essential features such as high temperature performance with low power usage, high strength, and robustness of thin films in tough environments such as heating elements in thermal socks. Hence, in this paper, we demonstrated laser induced graphene (LIG) as a suitable candidate for wearable thermal applications. LIG heaters were fabricated using a cost effective and environmentally friendly technique based on photothermal ablation of polyimide substrate using a 50 W CO 2 laser. The heat flux of LIG heater was improved by stacking multiple films while their electrical connections are made in parallel. Upon joule heating, the heaters had excellent electrothermal performance, fast and stable response, achieving temperature of 195 °C using a relatively low DC voltage of 10 V. Most importantly, they showed good durability after bending, washing and repeated heating and cooling cycles. Due to these advantages, the LIG-based thin film heaters have potential as reliable and low-cost heating elements for variety of tough applications such as defrosting and wearable thermal pads. [ABSTRACT FROM AUTHOR]

• Cobalt (Co) doping improves the electrochromic properties of the films. • Nickel (Ni)-Co-oxide films exhibit high transparency in the visible region. • Ni-Co-oxide films with high coloring efficiency and response time. This paper fabricates novel electrochromic films through the sol-gel spin coating of nickel (Ni) and tunable cobalt (Co) atoms. The particle size, band gap, conductivity, and response time of the electrochromic films were improved by accurately adjusting the doping ratio of Co atoms from cobalt acetate. According to the results of scanning electron microscope and X-ray diffraction, the particles size of the Ni-Co oxide film decreased from 9 nm to 25 nm, with the increase in Co content. The reduction of the band gap enhanced the film conductivity, resulting in better electrochromic properties. The electrochemical and optical measurements show the excellence of the film in switching time and coloring efficiency: thanks to incorporating Co atoms, the switching time was shortened from 15.2 s to 10.2 s, and the coloring efficiency was increased from 35.57 to 42.5 cm2 C−1. Overall, the proposed film has a promising future for electrochromic applications. [ABSTRACT FROM AUTHOR]

• Successful fabrication of superhydrophobic Ni-Zn electrodeposited coatings. • Employing power spectral density (PSD) analysis to describe hierarchical structures. • Linking the wettability of coatings to PSD parameters to establish a relationship. • Introducing superhydrophobicity index to predict wettability behavior of surfaces. This paper aims to establish a quantitative relationship between wettability and surface morphology. The wettability of surfaces is highly dependent on surface morphology, and this relationship will be explored using either conventional roughness parameters or power spectral density (PSD) derived parameters. To investigate the effect of surface morphology on wettability, various Ni-Zn coatings with different hierarchical surface morphologies were electrodeposited on copper substrates. The coatings exhibited hydrophobic behavior with apparent contact angles ranging from 105° to 155°, depending on the shape, size, and arrangement of their surface features. Although conventional roughness parameters like S q and S pc influenced the wettability of the coatings, their absolute values could not accurately predict superhydrophobic behavior. Therefore, the PSD analysis was used as an alternative approach to predict the wettability behavior of the coatings by distinguishing between nano- and micro-features. The results revealed that a superhydrophobicity (SH) index could be obtained from the PSD model to predict superhydrophobic properties. Coatings with an SH index below 0.32 exhibited a contact angle greater than 150°, regardless of their deposition parameters. The findings suggest that surface roughness plays a significant role in controlling the wettability of Ni-Zn coatings, and the SH index is a useful tool for predicting the superhydrophobic properties of these coatings. [ABSTRACT FROM AUTHOR]

• GeTe films fabrication by.pulsed laser deposition method. • Different structures of GeTe films are controlled by adjusting the growth temperature. • The photodetector of GeTe film exhibits excellent photoelectric performance at near-infrared. GeTe, with its narrow band gap and excellent carrier mobility, is a promising material for near-infrared (NIR) photodetector. In this paper, the NIR photoelectric properties of GeTe films grown by pulsed laser deposition were systematically studied. The microstructures of GeTe films can be controllably obtained by adjusting the substrate temperature. The photodetectors based on the GeTe films grown at 250 ℃ present excellent photoelectric properties with a responsivity of 0.98 A W-1, a detectivity of 1.08 × 109 Jones, and external quantum efficiency of 114.1% under the 1064 nm laser illumination at room temperature. Such excellent properties were primarily attributed to the interaction of hole trapping and electron-hole pair recombination. These photoelectric properties indicate that GeTe films have immense potential for NIR photodetection devices. [ABSTRACT FROM AUTHOR]

• The effect of annealing on the properties of chromium-gold films was investigated. • The critical annealing temperature of chromium-gold interdiffusion is presented. • Thin film mechanical properties after annealing were studied by nanoindentation. • The optimized annealing temperature for chromium-gold films was presented. Efficient mechanical properties of thin gold films on dielectric substrates are essential in micro-electro-mechanical systems applications. Hence, the film performance should be optimized via thermal treatment. In this paper, gold films with a nominal thickness of 100 nm and a chromium adhesion layer of 10 nm are deposited on the fused glass substrate. Annealing temperature dependency of the mechanical and structural properties of chromium-gold films is carefully investigated. The surface, cross-sectional morphology, hardness, Young's modulus, adhesion, stress, and conductivity of the chromium-gold bilayer film are explored for the annealing temperature range from 100 °C to 700 °C. The results show that the transition point temperature varies for different properties. The transition point at 200 °C for the adhesion and resistivity can be attributed to the improvement of the crystalline state caused by annealing. When the annealing temperature reaches 300 °C, Young's modulus, and the hardness are reduced, and the residual stress is minimized. Significant diffusion of chromium atoms into the gold layer is observed for the annealing temperature of 400 °C, which alters the initial structure of the bilayer films and modifies film properties. Moreover, resistivity reaches a maximum value, and the internal stress starts to increase, which is caused by the diffusion of the chromium film. Consequently, the definite annealing temperature needs to be selected for the required film properties. [ABSTRACT FROM AUTHOR]

• Potassium oleate (PO) can inhibit corrosion of copper (Cu) and cobalt (Co). • A small amount of PO can increase the removal rate of Co. • PO can work in synergy with fatty alcohol polyoxy ethylene ether. As the feature size of integrated circuit drops down to 20–14 nm, cobalt (Co) is used as the barrier layer material for multilayer copper (Cu) wiring. The chemical mechanical polishing (CMP) process of Cu film has developed from a combined rough polishing and fine polishing to a one-step polishing, which needs to stop on the Co barrier layer. So the removal rate (RR) of Co should approach zero to meet the requirement of higher RR selection ratio of Cu and Co. Inhibitors in the Cu film slurry play an important role for controlling the RR during CMP process. In this paper, the anionic surfactant potassium oleate (PO) was selected as a key corrosion inhibitor in Cu film CMP to enhance the RR selection ratio of Cu and Co. The complexation and corrosion inhibition mechanisms between PO and Cu or Co were revealed by electrochemical measurements, X-ray photoelectron spectroscopy and scanning electron microscopy measurements. It was found that the rapid complexation of a small amount of PO with Co2+ could increase the Co RR. However, with a higher concentration of PO, the effective catalysis caused the conversion of cobaltous hydroxide to tricobalt tetraoxide, and thus resulted in a lower Co RR. With the addition of the nonionic surfactant called fatty alcohol polyoxy ethylene ether (JFCE), the morphology of the PO aggregates changes to spherical, which weakened the inhibiting effect of PO on Cu RR, and thus a higher Cu RR and RR selection ratio of Cu and Co was achieved. The synergistic action mechanism of PO and JFCE on Cu and Co surfaces was analyzed systematically. The present work provides an idea that surfactants are excellent candidates for metal inhibitors. [ABSTRACT FROM AUTHOR]

• The microstructure and electrical conductivity of In 2 O 3 and indium tin oxide (ITO) films were characterized. • The high temperature stability of In 2 O 3 -ITO thermocouples is improved. • Small temperature drift rate holding at 1300 °C more than 7 h. The complex internal structure of the aero-engine and the high-temperature, high-pressure, and high-speed airflow make it difficult to measure the internal temperature. Indium tin oxide (ITO) and In 2 O 3 films have been studied for their application in high-temperature thermocouples and strain gauges. Due to their large Seebeck coefficient and high-temperature stability, ceramic thin-film thermocouples are expected to be used at high-temperature measure. In this paper, ITO-In 2 O 3 thermocouples were fabricated by magnetron sputtering. Besides, the electrical properties of the air-annealed and two-step nitrogen-annealed thermocouples were compared, including the repeatability of thermoelectric response after multiple thermal cycles and the drift rate during the high-temperature duration. The microstructure and electrical conductivity of both the as-deposited and post-annealed ceramic thin films were tested respectively. The result shows that the resitivity and Seebeck coefficient of the thin films annealed in nitrogen is reduced, but the stability at high temperature is greatly improved. [ABSTRACT FROM AUTHOR]

• Optical and structural properties of pure and W doped VO 2 are reported at 25°C and 85°C. • Point-by-point method provides a robust determination of the optical properties. • Correlation between refractive index and thickness of V1-xWxO2 films are eliminated. • Transition temperature is lowered by increasing the concentration of W doping. • Coexistence of monoclinic and rutile structures in V1-xWxO2 for x = 3% at 25°C. Vanadium dioxide is one of the most promising materials that can be used to control and tune in real time the optical properties of nanoscale devices due to its ability to perform a Metal-Insulator Transition (MIT). In this paper, we report the optical and structural properties of undoped and W-doped V 1-x W x O 2 vanadium dioxide thin films deposited on oxidized silicon substrates using magnetron sputtering. The structural properties determined by X-ray diffraction showed not only the transition from a monoclinic to a rutile phase when crossing the metal–insulator transition temperature (T M I T) but also a coexistence of phases for the tungsten-doped VO 2 even at room temperature. It is also shown that T M I T decreases from 69.6°C to 41.6°C as x increases from 0 to 3%. A point-by-point fitting method is proposed to reliably extract the refractive index and extinction coefficient from spectroscopic ellipsometry measurements as a function of temperature and tungsten concentration. This approach avoids all the correlations between the thickness and the refractive index well known in absorbent films calling into question the uniqueness of the results. The dielectric function is then calculated from the point by point refractive index. A model based on Tauc-Lorentz oscillators in the insulating phase to which a Drude component is added in the metallic phase provides information on the levels of the energy bands and the plasma frequency of the films. The calculation of reflectance and transmittance of V 1-x W x O 2 thin films highlights the effect of W doping on thermochromic performance. [ABSTRACT FROM AUTHOR]

• Several strategies for improving the photo-activity of TiO 2 NWs are explored. • NWs doping was performed by a new strategy. • Fe doping improves the photocatalytic activity in the visible range. • Pt nanoparticles deposition improves the activity in the UV and Vis range. • Thermal annealing in reductive environment improves the photoactivity. In the present paper, an investigation of the structural, optical, and photo-catalytical properties of TiO 2 nanowires (NWs) was conducted. The NWs were synthesized on a Si substrate by thermal oxidation of a thick (4 µm) Ti film covered by a thin (∼ 5 nm) Au film. The annealing process at 750 °C produced a 1.7 μm thick NWs TiO 2 layer over a 3 μm thick TiO 2 film. Characterization techniques show that TiO 2 NWs are in rutile phase and have gold nanoparticles on top. Fe-doped TiO 2 NWs were synthesized to increase photoactivity in the visible range. The doping was performed using an unusual strategy, that is, implanting Fe+ ions into the Ti layers before the growth of the TiO 2 NWs. The defectiveness introduced by the ion implantation is avoided and precise control of the doping is achieved. The photocatalytic properties were studied by following the degradation of methylene blue. In order to increase the photo-degradation rate under UV light of undoped NWs, two different strategies have been followed: 1) deposition of Pt nanoparticles on the front or on the rear side of the samples, and 2) thermal annealing in a reductive environment. A three-fold activity enhancement is obtained and discussed. Photocatalytic activity in the visible range was also measured for the Fe-doped samples, showing good activity, which was further improved by using the same strategies implemented under UV irradiation. [ABSTRACT FROM AUTHOR]

The present paper reports a complete study on the correlation between structure, morphology, and magnetic properties of (111)-oriented cobalt ferrite (CoFe 2 O 4) thin films with varying film thickness. The CoFe 2 O 4 (CFO) thin films were deposited on Pt-coated Si substrate by pulsed laser deposition (PLD) at 550 °C. The x-ray diffraction (XRD) data confirms the (111)-oriented growth of the cobalt ferrite films. The in-plane morphology of the films in the field emission scanning electron micrographs ensure the Stranski–Krastanov growth mechanism, and the atomic force micrographs confirms the effect of lattice relaxation on the morphology of the films with varying thickness. The possible cation distributions for the samples were determined from the Raman spectroscopy, which revealed the crystal structure-magnetic property correlations in cobalt ferrite films. The magnetic hysteresis (M − H) loops show a significant spin reorientation by showing the variation between the in-plane (IP) and out-of-plane (OP) magnetization. The presence of a kink on the OP M − H loops and its variation with film thickness clearly establishes the existence of competing magnetic anisotropies in the films. The high coercivity (H C) values observed for OP magnetization of cobalt ferrite films with thicknesses 115 nm and 125 nm may be explored for possible room-temperature (RT) device applications. • Structure–property correlations in CoFe 2 O 4 (111) thin films have been discussed. • Variation of magnetic parameters with film thickness suggests a change of magnetic orientation. • The cation distribution is responsible for the magnetic moment in CoFe 2 O 4 films. [ABSTRACT FROM AUTHOR]

This paper presents a flexible piezoelectric device that has been realized by depositing lead zirconate titanate (PZT) thin films by chemical solution deposition (CSD) on a commercial aluminum foil as a substrate. The thermal treatment required for the crystallization of the PZT thin films leads to the oxidation of the substrate and a parasitic intermediate layer of alumina (Al 2 O 3) is formed between the substrate and the first PZT layer. The comparison with and without the use of a conductive ruthenium dioxide (RuO 2) interlayer, which can shunt the insulating alumina layer, showed the influence of the latter on the different characteristics of the material. The thickness of the alumina layer on the surface of the aluminum substrate after deposition of the PZT film (≈ 39 nm) was determined by calculation and confirmed by transmission electron microscopy (TEM). Dielectric characterization of the sample without considering this layer gives the permittivity of the Al 2 O 3 /PZT bilayer and not the active material alone (PZT). A relative permittivity value of 313 is measured against 558 for the single PZT layer if the alumina layer is taken into account, which means a decrease of 44%. The piezoelectric characterization is also influenced by the alumina layer, the piezoelectric coefficient is 14 pC/N while it is 26 pC/N when this layer is taken into account. This study evidences and quantitatively evaluates the influence of the oxidation layer (Al 2 O 3) on the dielectric and piezoelectric characteristics and mechanical energy harvesting performances. [ABSTRACT FROM AUTHOR]

• PC 6 monolayer exhibits large storage capacity of 1496.23/1301.07/780.63 mA·h·g−1 for Li/Na/K ion. • Small diffusion barriers and relatively low open-circuit voltages are found for the anode of PC 6 monolayer. • The saturation adsorption systems of PC 6 can maintain good stability even at the temperature of 400 K. The development of two-dimensional (2D) materials in anode has been believed as a significant research direction to promote the innovation of alkali metal-ion batteries. Lately, PC 6 monolayer, a neoteric material, has stimulated people's research enthusiasm owing to its outstanding thermodynamic and electrical natures. In this paper, by employing the first-principles calculation method based on density function theory, the feasibility of PC 6 monolayer acting as an anode in alkali metal-ion batteries has been systematically evaluated. The simulation results indicate that, when acting as anode material, the PC 6 monolayer can not only provide effective adsorption interaction for metal ions which is beneficial for inhibiting the formation of clusters, but also can furnish satisfactory storage capacity (1496.23 mA·h·g−1 for Li, 1301.07 mA·h·g−1 for Na, and 780.63 mA·h·g−1 for K). Meanwhile, PC 6 monolayer can supply appropriate average open-circuit voltages (0.48/0.40/0.64 V for Li/Na/K), which are all within the ideal voltage range of anode material. Importantly, the appraised diffusion behaviors further reflect the isotropic property and wonderful migration performance (0.42/0.46/0.29 eV for Li/Na/K) of PC 6 monolayer for metal ions. Remarkedly, the ab initio molecular dynamics simulations results illustrate that these saturated adsorption systems have excellent deformation resistance at a high temperature of 400 K. These exciting performances endow the PC 6 monolayer with promising application prospects as an anode in alkali metal-ion batteries. [ABSTRACT FROM AUTHOR]

• Hydrogenated nanocrystalline silicon (nc-Si:H) thin films were fabricated by MS. • H 2 flow of 0, 2.5, and 5 sccm were applied for Si dangling bonds passivation. • Fraction of Si nanocrystallites was increased with increasing H 2 rate and annealing. • Phonon confinement in 3.8 nm size Si nanocrystallites was found from raman analysis. The main objective of this paper is to produce the hydrogen-free and hydrogenated nanocrystalline silicon (nc-Si : H (x)) thin films deposited onto the single-crystalline Si(100) wafer by radio-frequency magnetron sputtering (RF-MS) at a substrate temperature of ∼ 300 K. Sputtering was effectuated by a microwave plasma in a mixture of argon and hydrogen (Ar + (H 2 (x)) gasses taken at different proportions of hydrogen dilution: x = 0, 2.5, and 5 sccm (standard cubic centimeter per minute). The deposition rates of the nc-Si : H were fully controlled, and the thickness of these films was ∼ 200 and 300 Å. Pt -capping layer was deposited in order to protect the nc-Si : H layer from oxidation. The thickness of the capping layer was fixed at ∼ 5 Å. The effects of the hydrogen flow rate and post-growth thermal treatment on the crystalline structure and morphology of as-grown nanocrystalline silicon thin films were systematically investigated by ultraviolet and x-ray photoelectron spectroscopy (UPS and XPS), atomic force microscopy (AFM), grazing incidence x-ray diffraction (GI-XRD) and micro-Raman spectroscopy methods. From the measured data, the average nanocrystallite sizes, surface morphology and other important characteristics of these thin films were analyzed. The grown nc-Si : H thin films may be used as a semiconducting electrode material for electrochemical proton production, which is of great technological importance, especially for solid-state electrochromic device applications. [ABSTRACT FROM AUTHOR]

• Silica aerogel films are demonstrated with a very low refractive index, near n∼1.1. • The high bandgap makes silica aerogel resistant to contamination-induced laser damage. • Silica aerogels will enable multilayers using only silica, with high damage resistance. • The thin film aerogels were synthesized by a two-step acid/base catalyzed technique. • The aerogels displayed scattering comparable to the substrates and low absorption. Silica aerogels synthesized by different techniques have been studied for their electrical and thermal insulating properties, mostly in their bulk structures; however, the optical properties of a silica aerogel thin film have remained largely unexplored. Due to their high porosities, silica aerogel thin films may be useful as very low-index optical materials, especially in multilayer coatings for high intensity and high-power lasers, where the large bandgap of silica is particularly valuable. In this paper, silica aerogel thin films were fabricated by spin-coating a silica sol, derived from a two-step acid/base catalyzed technique at an ambient pressure, on fused silica substrates. The films showed very low refractive indices (n) around 1.1 (approximately 72% porosity) and low absorptions between about 6 and 16ppm, lower than plasma-enhanced chemical vapor deposition (PECVD) comparison films. Optical scatterings of the silica aerogel films were measured and found to be comparable to a PECVD silica film and a bare fused silica substrate, with most films showing slightly higher scattering but one film showing lower. The laser-induced damage thresholds (LIDT) of all films were measured using carbon particle contamination, which allows testing over statistically large areas using continuous wave (CW) laser illumination. The LIDT of silica aerogels was similar to that of pure high-density silica and much higher than that of other common high-LIDT films such as hafnia and alumina. Most damage spots on silica aerogel samples only showed slight discoloration at irradiance levels of 150 kW/cm2 (1.5 × 109 W/m2), while similar tantala high reflectivity coatings failed catastrophically at 75 or 86 kW/cm2 (7.5 × 108 or 8.6 × 108 W/m2). Moreover, aerogels performed somewhat better than PECVD silica, where most damage occurred at a lower irradiance level of 100 kW/cm2 (1 × 109 W/m2) with a larger discolored spot. [ABSTRACT FROM AUTHOR]

• Enables the Mueller matrix ellipsometry based integrated metrology OCD. • An azimuthal sensitivity analysis and ridge regression (ASA-RR) method is proposed. • Measurement accuracy is significant improved. Mueller matrix ellipsometry (MME) is commonly applied by the standalone instruments in semiconductor manufacturing process for films and nanostructures characterization. However, MME is rarely used in the integrated metrology optical critical dimension (IM OCD) tools due to the difficulty in extracting the parameters under varied azimuth angle conditions, which is induced by the rotation of R-θ wafer stage adapted to the restricted space. When the measurements on a same wafer are achieved under multiple azimuthal angles, the measured nanostructure parameters usually mismatch the baseline values provided by the manufacturer, and therefore lead to the unacceptable accuracy loss. In this paper, we propose an azimuthal sensitivity analysis and ridge regression algorithm (ASA-RR) to enable the MME-based IM OCD. The sensitivity to variability in azimuth angles is calculated by the local sensitivity analysis algorithm, and the result of which is applied as the weight factor for the spectrum input in the ridge regression. Experiments demonstrate that the ASA-RR algorithm provides more accurate results for the IM OCD, which satisfy the requirements in manufacturing. [ABSTRACT FROM AUTHOR]

1 Ni-Co-La 2 O 3 composite coating was deposited on SUS 430 by electroplating. 2 The Ni-Co-La 2 O 3 coating decreased oxidation rate of the steel. 3 The formed Cr 2 O 3 scale on the Ni-Co-La 2 O 3 coated steel had the thinnest thickness. 4 High electrical conductivity was observed for Ni-Co-La 2 O 3 composite coating. The application of spinel coatings has been proposed to overcome the difficulties in ultilizing ferritic stainless steel as interconnection. In this paper, a La 2 O 3 -doped (Ni,Co) 3 O 4 coating containing 15 wt% La 2 O 3 was synthesized on a SUS430 stainless steel via codeposition, followed by thermal conversion of the deposited layer in air at 800 ℃ for 1000 h. The surface and cross-sectional microstructure of the samples is analyzed by scanning electron microscope, and X-ray diffraction. The results reveal that a tri-layer oxide structure with Co 3 O 4 outer layer, (Ni,Co,Fe) 3 O 4 /(Ni,Co) 3 O 4 /(Ni,Co)O middle layer and (Mn,Cr) 3 O 4 /Cr 2 O 3 inner layer is developed on the Ni-Co-La 2 O 3 coated steel. This work is designed to elucidate the diffusion behavior of elements and the effect mechanism of the La 2 O 3. The addition of La 2 O 3 inhibits the growth of Cr 2 O 3 at the coating/substrate interface. Moreover, a higher electrical conductivity has been achieved for the La 2 O 3 -doped coating sample. [ABSTRACT FROM AUTHOR]

• A library search combined with Levenberg-Marquardt method is proposed. • Presorted KD-tree speeds up library search. • Time cost is significantly reduced while the accuracy is maintained. Optical scatterometry has been widely used for nanostructure metrology in integrated circuit (IC) given the fast, low-cost, non-contact, non-destructive, and in-line technique. Library search is a common solution for optical scatterometry, but the deterministic error in this method is hard to be eliminated due to the limitation of the grid interval in the spectral library. Another solution is the nonlinear regression algorithm, which faces difficulty in practical applications in meeting the in-line real-time requirements as it involves the time-consuming rigorous coupled-wave analysis (RCWA) calculations in the forward modeling. In this paper, we propose a combination of library search and Levenberg-Marquardt (LSLM) algorithm to solve the problem. We apply a presorted K-dimensional tree (KD-tree) algorithm to speed up searching the initial parameters in the spectral library and replace the time-consuming RCWA calculations with the Taylor expansion in the spectral library to compute the Jacobian matrix in the Levenberg-Marquardt (LM) procedure. Simulations and experiments demonstrate that the results in the proposed method are accurate, and in particular, the speed is much faster than that in previous methods. [ABSTRACT FROM AUTHOR]