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In this study, we successfully synthesized three gallium oxide thin films on (0001)-faceted Al 2 O 3 substrates using hydrogen-reduced chemical vapor deposition (CVD) at different deposition temperatures, resulting in distinct morphologies and crystalline phases. These films consist of two pure-phase β-Ga 2 O 3 films and one mixed-phase film comprising both β- and ε-Ga 2 O 3 phases. The mixed-phase samples were subsequently annealed at high temperatures to obtain pure-phase β-Ga 2 O 3 thin films. Furthermore, by precisely controlling the growth temperature, we achieved in-situ formation of Ga 2 O 3 nanostructures (nanowires and nanoribbons) on the surface of the β-Ga 2 O 3 thin films. The presence of different dominant crystal planes in the samples was confirmed through X-ray diffraction analysis (XRD) for verification purposes. In directly grown β-Ga 2 O 3 films, the (−201) plane emerged as the primary crystallographic plane, while both the (−201) and (401) planes dominated in β-Ga 2 O 3 films obtained via ε-Ga 2 O 3 film annealing. Raman spectroscopy findings further supported these observations regarding the crystalline phase of the films as observed through XRD analysis. Scanning electron microscopy (SEM) images revealed distinct film morphologies resulting from variations in deposition temperatures. A flatter surface was observed when a higher proportion of ε-Ga 2 O 3 was present in the film, however, regular cracking occurred after annealing. Atomic Force Microscope (AFM) images demonstrated that at a deposition temperature of 800 °C, regular steps were present on the film's surface. Mixed-phase films exhibited hillock morphology that disappeared after annealing, leading to a decrease in the surface roughness in root mean square (RMS) value. By elevating the growth temperature, a significantly enhanced density of gallium oxide nanoribbons can be seamlessly integrated onto the film surface. The transferred nanoribbons exhibit an ultra-thin profile with a minimum thickness of merely 12 nm, rendering them more slender and economically advantageous in comparison to conventional mechanical stripping methods. This study presents a CVD-based approach for growing gallium oxide thin films with varying morphologies by employing temperature modulation and demonstrates an innovative one-step method for growing nanostructures on gallium oxide films in situ, providing valuable insights for future device development involving gallium oxide. [ABSTRACT FROM AUTHOR]

In this work, SnO2 thin films are deposited by drop–dry deposition (DDD), which is a simple, low-cost chemical technique for thin film deposition. The deposition solution contains Na2SnO3 as the Sn source, and is highly stable without spontaneous reactions in the solution. The solution is dropped on a substrate heated to 60°C on a heater plate. According to Auger electron spectroscopy, the deposit will be stoichiometric SnO2. The film is n-type and transparent in the visible range. The pn heterostructure is fabricated by depositing SnO2 on p-type NiO. The NiO film is also fabricated by DDD. Ni(OH)2 is deposited using a solution containing Ni(NO3)2 and NaOH, and then is converted to NiO by annealing at 400°C. The SnO2/NiO structure is transparent in the visible range and shows clear rectification properties and photovoltaic effects. Thus, a transparent solar cell is successfully fabricated by DDD. [ABSTRACT FROM AUTHOR]

Several thin film deposition techniques for oxide semiconducting materials have been developed. In this study, we employed an innovative technique known as chemical wet and dry (CWD) technique to deposit undoped SnO2 thin films on soda lime glass (SLG) and quartz substrates. This approach is an upgraded variant of the dip-coating process, involving controlled substrate withdrawal and in situ annealing in an inert gas atmosphere, ensuring uniform thickness control and contamination-free coating. The presence of a well-made undoped SnO2 thin film on SLG and quartz substrates was confirmed using grazing incidence x-ray diffraction (GIXRD). The films exhibit a mixed state of crystalline and amorphous nature, characterized by the presence of broad, strong peaks, suggesting Debye–Scherrer broadening. Furthermore, field emission scanning electron microscopy (FE-SEM) examinations showed an even distribution of particles on the film's surface, with particle sizes measuring between 10.58 nm and 9.17 nm. Fourier transform infrared (FT-IR) spectroscopy was utilized to detect functional groups within the film. This determination was substantiated by energy-dispersive x-ray spectroscopy (EDAX) analysis, confirming the film's composition. Optical investigations revealed that the films deposited on both SLG and quartz substrates possess remarkable transparency, exceeding 70% in the visible spectrum. The bandgap values range from 3.05 eV to 3.02 eV for SnO2 thin films deposited on SLG and quartz substrates, respectively. The variations in Hall mobilities, attributed to the impact of grain size, have been recognized, confirming the material's n-type characteristics as confirmed by Hall effect assessments. These prepared samples show promising prospects for use in forthcoming transparent conductive and optoelectronic devices, based on the aforementioned data and discoveries. [ABSTRACT FROM AUTHOR]

Silicon nitride (Si3N4) materials are widely used in the electronics, optoelectronics, and semiconductor industries, with Si3N4 thin films exhibiting high densities, high dielectric constants, good insulation performance, and good thermal and chemical stability. However, direct deposition of Si3N4 thin films on glass can result in considerable tensile stress and cracking. In this study, magnetron sputtering was used to deposit a Si3N4 thin film on glass, and a silicon dioxide (SiO2) thin film was introduced to reduce the Si3N4 binding force and stress. The effect of the SiO2 layer thickness on the SiO2/Si3N4 multilayered thin film was explored. The results indicated that the introduction of the SiO2 layer could improve the weak adhesion characteristics of Si3N4 thin films. Moreover, sputtering the SiO2 layer to 150 nm resulted in the highest hardness and transmittance of the SiO2/Si3N4 multilayered thin films. The findings of this study lay a solid foundation for the application of Si3N4 thin films on glass. [ABSTRACT FROM AUTHOR]

Thin film technology is significant in technological progress and modern research because it allows for the production of optoelectronic devices with improved characteristics. Because of its superior chromatic efficiency, tungsten oxide (WO3) is one of the best candidates for energy-saving applications. In this study, undoped and tin (Sn)-doped WO3 films were grown on top of WO3 seed layers directly by a facile hydrothermal route at a temperature as low as 110∘C for 24 h. The seed layers were also deposited on top of glass substrates using spray pyrolysis. The results of tin doping on the structural, optical, and morphological characteristics of the WO3:Sn films were studied. X-ray diffraction patterns show that peak intensities increase significantly by adding Sn and the films' crystallinity was improved by rising Sn content. In the visible region, the average optical transmittance is around 13% and the optical bandgap changes from 2.61 eV to 2.81 eV, by increasing the dopant amount. Finally, the room temperature photoluminescence of samples shows intense green light emissions. The results of this research can be beneficial for the fabrication and performance optimization of electrical and optical devices such as gas sensors, electrochromic devices, and photosensors. [ABSTRACT FROM AUTHOR]

Third-generation solar cells have emerged as a potential solution to the effectiveness and stability issues encountered in conventional solar technology. This study focuses on the characteristics of copper-zinc-tin-sulfide (CZTS) thin films inside this innovative architectural framework, which is an important step toward improving third-generation solar cells by incorporating a p-type silicon layer. This integrated method provides a versatile and manageable setting for film deposition, underscoring the effort put into creating high-quality CZTS thin films. Using X-ray diffraction (XRD), the study assessed the structural change of CZTS films after annealing, finding that kesterite phases were dominant. Images captured by a scanning electron microscope (SEM) reveal the microstructure and surface morphology of CZTS-coated Silicon nanowires (Si-NWs). A detailed analysis of the current-voltage characteristics provides evidence of the operational potential of the Si-NWs-CZTS coated solar cell. Significant performance parameters observed include a Voc value of 0.45 ± 0.02V, Isc value of 8.25 ± 0.30 mA/cm², FF value of 24 ± 2%, and η value of 1.0 ± 0.1%. The encouraging results indicate the capacity of using P-type silicon to enhance the performance of third-generation solar cells. [ABSTRACT FROM AUTHOR]

Ru films are grown on Pt, TiN, and SiO2 substrates via atomic layer deposition (ALD) using Ru(II)(η5‐C7H7O)(η5‐C7H9) as the novel Ru metalorganic precursor and O2 as the reactant. The ALD self‐limiting film growth is confirmed at the low temperature of 200 °C by manipulating the injection time and purge time of the Ru precursor and O2, and the saturated growth per cycle is 0.22 Å cy−1. It is confirmed that the combustion reaction occurs during the deposition process from the formation of the H2O and CO2 by‐products. Thin films with a low resistivity of 17–19 µΩ cm are grown at a thickness of ≈15 nm. The Ru incubation times are remarkably short at 200 °C (negligible on Pt, ≈30 cycles on TiN and SiO2), but increase with increasing temperature. The energy dispersive X‐ray mapping image of the Ru film on the pattern in which TiN is formed on SiO2 shows that the Ru film with a novel precursor has the intrinsic substrate selectivity at the deposition temperature of 300 °C. Furthermore, the substrate affects the properties of the Ru film. Particularly because Ti serves as an oxygen reservoir, a relatively large amount of RuOx is produced on the TiN substrate. [ABSTRACT FROM AUTHOR]

Solid‐state batteries (SSBs) that use solid electrolytes instead of flammable liquid electrolytes have the potential to generate higher specific capacity and offer better safety. Magnesium (Mg) based SSBs with Mg metal anodes are considered to be one of the most promising energy storage candidates, because it gives high theoretical volumetric capacities of 3830 mAh cm−3. Here, we demonstrate an atomic layer deposition (ALD) process with a double nitrogen plasma process that successfully produces nitrogen‐incorporated magnesium phosphorus oxynitride (MgPON) solid‐state electrolyte (SSE) thin films at a low deposition temperature of 125 °C. The ALD MgPON SSEs exhibit an ionic conductivity of 0.36 and 1.2 μS cm−1 at 450 and 500 °C, respectively. The proposed ALD strategy shows the ability of conformal deposition nitrogen‐doped SSEs on pattered substrates and is attractive for using nitride ion‐conducing films as protective or wetting interlayers in solid‐state Mg and Li batteries. [ABSTRACT FROM AUTHOR]

This work aims to investigate the effect of different cyclic voltammetry scan rates on silver nanoparticles deposition on ITO-coated glass aiming to obtain improve its optical and electrical properties. The deposition was evaluated using different physical, chemical and optical characterization techniques, such as SEM, XRD, FTIR, UV–visible and electrochemical tests. Cyclic voltammetry was used to measure the Ag deposition at two different scan rates (20 CV at 10 mV/s and 100 CV at 30 mV/s). The characterization results have confirmed the formation of a homogeneous crystal layer of silver on ITO, which exhibited high transmittance in the visible light region. According to the cyclic voltammetry measurements, the outer spheres of the Ag NPs associated with the redox reaction illustrate the typical reduction and oxidation waves of Ag in the range of (−100 to +700) mV. The quantification using Cyclic voltammetry measurements has shown that the Ag nanoparticles deposition on ITO thin films are inversely proportional to the scan rates; in other words, higher deposition is obtained at lower scan rates. [ABSTRACT FROM AUTHOR]

Impurities can be incorporated during thin film deposition, but also can originate from atmosphere exposure. As impurities can strongly affect the composition—structure—property relations in magnetron sputter deposited thin films, it is important to distinguish between both incorporation channels. Therefore, the impurity incorporation by atmosphere exposure into sputtered Mg, Al, and Ca thin films is systematically studied by a variation of the deposition temperatures and atmosphere exposure times. Deposition temperature variation results in morphological modifications explained by considering surface and bulk diffusion as well as grain boundary motion and evaporation. The film morphologies exhibiting the lowest oxygen concentrations, as measured by energy dispersive X-ray spectroscopy, are obtained at a homologous temperature of 0.4 for both Mg and Al thin films. For Ca, preventing atmosphere exposure is essential to hinder impurity incorporation: By comparing the impurity concentration in Al-capped and uncapped thin films, it is demonstrated that Ca thin films are locally protected by Al-capping, while Mg (and Al) form native passivation layers. Furthermore, it can be learned that the capping (or self-passivation) efficiency in terms of hindering further oxidation of the films in atmosphere is strongly dependent on the underlying morphology, which in turn is defined by the growth temperature. [ABSTRACT FROM AUTHOR]

The control of thin film deposition is an important issue in a wide range of applications, ranging from optoelectronic devices to active components in energy storage technologies. In this sense, the successive ionic layer adsorption and reaction (SILAR) technique has gained increasing interest from the scientific community for its simplicity, efficiency, and versatility in depositing several types of thin film materials of great technological interest over a variety of substrates, with tunable properties depending on the deposition parameters. Regarding the limitations and problems induced by using the conventional manual SILAR process, we present the design and implementation of a new automatic low-cost SILAR system for further developing and improving thin film deposition quality and reproducibility while avoiding operator fatigue. Our designed system relies on a motorized mobile platform with 1.8 degrees of freedom equipped with a multiple substrate holder, a control board in order to regulate the horizontal and vertical axis speed, and finally, an improved graphical user interface for controlling and monitoring the main parameters such as displacement speed in x and y directions, growth cycles, immersion, and rise time for each beaker. More particularly, the present study aims to improve the system's programming in order to allow the motor to reach its maximum speed at start-up, reduce the cycle time, make it more controllable, and overcome the problem of time delay between cycles. The performance of the system was assessed by depositing crystalline zinc oxide (ZnO) thin film. Scanning electron microscopy, X-ray diffraction, and ultraviolet/visible spectroscopy demonstrated a good correlation between the evolution of the number of deposition cycles with the crystallite/grain size and film thickness. Moreover, controlling the instrument allows obtaining thin films with good adhesion and homogeneity. All these advantages make this technology promising at the industrial scale. [ABSTRACT FROM AUTHOR]

In this study, we aimed to improve our understanding of the response mechanisms associated with the formation of CdS thin films. CdS thin film remains the most valuable option for many researchers, since it has shown to be an effective buffer material for film-based polycrystalline solar cells (CdTe, CIGSe, CZTS). We performed experimental and numerical simulations to investigate the effect of different thiourea concentrations on the characteristics of the CdS buffer layer. The experimental results reveal that an increase in thiourea concentrations had a direct effect on the optical results, with bandgap values ranging from (2.32 to 2.43) eV. XRD analysis confirmed that all deposited films were polycrystalline, except for [1/0.75], where there is no CdS formation. Electrical studies indicated that CdS with a molar ratio of [Cd]/[S] of 1 had the maximum carrier concentration (3.21 × 1014 cm−3) and lowest resistivity (1843.9 Ω·cm). Based on the proposed mechanism, three kinds of mechanisms are involved in the formation of CdS layers. Among them, the ion-by-ion mechanism has a significant effect on the formation of CdS films. Besides, modelling studies reveal that the optic-electrical properties of the buffer layer play a crucial role in influencing the performance of a CIGS solar cell. [ABSTRACT FROM AUTHOR]

Monoclinic β-phase Ga 2 O 3 , the most thermodynamically stable phase, is an interesting material for power electronics applications. In this study, we present an efficient approach, diverging from existing methods, for the successful deposition of β-Ga 2 O 3 thin films at low substrate temperatures without any post-annealing. Instead of relying on high substrate temperatures, we supplied sufficient thermal energy to the substrate by directly irradiating it with a 1064 nm ytterbium pulsed laser during RF sputtering. This eliminated the need for post-annealing and significantly reduced processing time. It also allowed for excellent control over the crystal structure and crystallinity formation of the thin films by providing excellent particle energy through heat transfer on the surface. The X-ray diffraction (XRD) scan of the sample deposited by irradiating a pulse laser to the substrate shows only three peaks corresponding to (−201), (−402) and (−603) of β-Ga 2 O 3 , indicating superior crystalline quality. The sample deposited at 2.5 mTorr working pressure maintained a thin film thickness of 207 nm and a grain size of 40.07 nm, and the energy band gap of the thin films was measured in the range of 4.45–4.64 eV. XPS, Auger, and PL optical analysis observed characteristic core-level peaks of β-Ga 2 O 3 and the suppression of oxygen vacancies due to the high binding energy. The oxygen content increased by 4.39 %, resulting in the O/Ga ratio rising to 1.19, which leads to a positive shift in the O 1s binding energy. Consequently, we demonstrated the induction of phase transition of Ga 2 O 3 into a stable β phase by introducing an in-situ pulse laser process during low temperature RF sputtering. These results have significant potential in various applications and are expected to contribute significantly to technological advancements. [ABSTRACT FROM AUTHOR]

Si–B–N ceramic hard films were prepared by injecting N 2 +SiH 4 +B 2 H 6 reaction gas into an argon DC arc plasma jet at reduced pressure. XPS, FT-IR, SEM, and microhardness tester were used to characterize the samples, and the optical properties of Ar discharge plasma jet with and without reaction gas injection were studied by a multichannel high-resolution spectroscopy and a wide spectral range spectroscopy. It is found that the deposited films are mainly composed of Si, B, N and O. The film surface presents a dense structure with hundred-nanometer-sized clusters, and the hardness of sample is greatly enhanced. When the reaction gas is injected into the plasma jet, the emission of excited atoms in the background plasma is greatly reduced, and the growth rate of Si–B–N film shows a significant downward trend as the reaction gas injection ring or substrate holder is moved away from the torch nozzle. A slight enhancement of background plasma emission is observed near the substrate surface with increasing the distance between gas injection ring and torch nozzle, which indicates that the suppression effect of the reactive gas injection on the background plasma emission and the activation efficiency of the reaction gas are weakened, thereby reducing the deposition rate. • SiBN films were prepared by injecting N 2 +SiH 4 +B 2 H 6 gas into an argon DC arc plasma. • The background plasma emission is greatly reduced when the reaction gas is injected. • The growth rate decreases as injection ring or substrate is moved away from nozzle. • The background emission near the substrate enhances as the ring is away from nozzle. [ABSTRACT FROM AUTHOR]

Thin film coatings are extensively used to enhance the physical and chemical properties of various materials by depositing a thin layer of coatings of different materials onto various substrates. Several deposition processes are available which are widely adopted by many manufacturing industries to meet such demands. To exploit the fullest potential of those deposition processes, it is often advised to operate them with the optimal combination of process parameters. In this research, a modified PROMETHEE (preference ranking organisation method for enrichment evaluation) method as an effective multi-objective optimisation tool is applied for identifying the optimal parametric combinations of two thin film deposition processes: silicon carbonitride thin film coating using a thermal chemical vapour deposition process and zirconium-containing diamond-like-carbon thin film coating using an unbalanced magnetron sputtering process. The derived optimal parametric combinations are validated based on developed regression equations, which exhibit that the proposed approach can attain better response values as compared to other popular optimisation techniques. The analysis of variance results and the developed surface plots further illustrate the influence of various deposition parameters on coating quality. [ABSTRACT FROM AUTHOR]

In this study, OW · WO emulsions, which are similar to the product formulation, were used for thin film deposition at high speeds. The evaluation of the developed thin films showed that the shear process during the application of OW emulsions caused coalescence deformation, which was related to the nonuniformity of the properties of the applied films. In contrast, the WO emulsion, which did not deform on the shear surface, formed a uniform coating film under all conditions from coating to drying. Therefore, it is important to determine a rheological measurement method to predict the unification processes of a product design that considers the coating properties. [ABSTRACT FROM AUTHOR]

The model to tailor the required chemical composition of thin films fabricated via multisource deposition, exploiting basic physicochemical constants of source materials, is developed. The model is experimentally verified for the two-source depositions of chalcogenide thin films from Ga–Sb–Te system (tie-lines GaSb–GaTe and GaSb–Te). The thin films are deposited by radiofrequency magnetron sputtering using GaSb, GaTe, and Te targets. Prepared thin films are characterized by means of energy dispersive X-ray analysis coupled with a scanning electron microscope to determine the chemical composition and by variable angle spectroscopic ellipsometry to establish film thickness. Good agreement between results of calculations and experimentally determined compositions of the co-deposited thin films is achieved for both the above-mentioned tie-lines. Moreover, in spite of all the applied simplifications, the proposed model is robust to be generally used for studies where the influence of thin film composition on their properties is investigated. [ABSTRACT FROM AUTHOR]

Acid rain is a major problem for animals, plants, buildings, and also for the top glass of photovoltaic (PV) solar panels and greenhouses. Air pollutants such as NOx, NH3, and H2S can mix with water in the atmosphere to form acid rain. It was discovered that atmospheric water vapor adsorbed on the surface of glass can also lead to corrosion of the glass surface. The purpose of this work is to obtain a protective film for glasses used in different domains such as solar cells, windows, stained glass windows from historical buildings, etc. Thin film deposited on glass must be protective against acid rain, transparent in the visible domain with a band gap up to 3.2 eV, and have a vitreous structure (glass). Electron beam (e-gun) technology is a deposition technique for producing high-purity and dense coatings in a short time. It is well known that Ta2O5 is an oxide with anticorrosive properties, but it is expensive and cannot form glass by itself. ZnO is an oxide known as a glass former, exhibiting good optical properties. In this paper, a thin film obtained by the deposition of ZnO and Ta2O5 on a glass substrate using e-gun technology are studied. The simulated acid rain effect on the structure, morphology, and optical properties of thin films are studied after a 65% nitric acid attack on the surface. The X-ray diffraction (XRD) pattern shows the vitreous state of the thin film with a composition 50%ZnO 50%Ta2O5 before and after the acid attack. The morphology, composition, and thickness of the film are investigated using scanning electron microscopy with energy dispersive spectroscopy (SEM/EDS) and profilometry. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mn doped SnO2 synthesized on Si(0 0 1) substrates via advanced pulsed laser deposition technique. • An increase in Mn doping concentration within SnO2 leads to a reduction in grain size. • As the Mn doping concentration increases, the magnetic behaviour changes from ferromagnetic to anti-ferromagnetic. • The reduction in grain size can result in a shift from ferromagnetic to antiferromagnetic behavior. • O2− ions play a pivotal role in inducing ferromagnetism in synthesized SMO film. SnO 2 is diamagnetic in nature and represent paramagnetic, ferromagnetic and anti-ferromagnetic behaviours after inducing Mn in the host matrix. Mn doped SnO 2 thin films prepared by PLD technique. XRD and AFM measurements confirm the reducing crystallite and grain size of the samples with increasing doping of Mn. In this research authors focused on magnetization effect of SMO thin films with the help of SQUID-VSM magnetometer. Magnetic analysis reflects strong ferromagnetic behaviour for (10 % Mn) doping and further increase upto (15 %) shift to ferromagnetic to anti-ferromagnetic behaviour. The above observation will be useful for the core elements for the spintronic devices. [ABSTRACT FROM AUTHOR]

Design, development and application of single source molecular precursors (SSPs) for the fabrication of IV-VI metal chalcogenide nanomaterials and thin films have been reviewed. SSPs from the inception of the field to till date to access these versatile materials are discussed in categorical manner. [Display omitted] • Opportunity and challenges of single source molecular precursor (SSP) route to nanomaterials and thin films have been presented. • Design, synthesis, spectroscopy and molecular structure of group IV metal–chalcogen complexes are summarized. • Application of these complexes as efficient SSPs for the preparation of group IV Metal chalcogenide nanomaterials and thin films are presented. • Effect of capping agent and reaction conditions on composition, morphology and optical properties of these materials are discussed. • Structure-property correlation and application of group IV Metal chalcogenides have been illustrated. Group IV metal chalcogenides (group IV MCs) have garnered significant attention from scientific fraternity owing to their distinct structural features and interesting electronic properties that could be exploited for diverse applications including energy conversion and storage, optoelectronic devices and sensors. However, to make group IV MCs commercially viable, it is imperative to evolve efficient, cost effective and scalable methods for their synthesis. Single source molecular precursor (SSP) mediated synthesis of group IV MCs is one such route which enjoys tremendous advantages over conventional solid state or dual precursor routes. Most importantly, SSP serve as a viable tool to afford phase pure group IV MCs with high reproducibility and excellent control over size and morphology in presence of suitable capping agents. This timely review provides a comprehensive overview of SSPs employed for accessing group IV MCs nanomaterials as well as thin films. Effects of various ligands on SSP performance have been rationalized. Additionally, precursors which can afford selective synthesis of different compositions or phase of group IV MCs by the choice of solvent, temperature and mode of decomposition have been critically assessed. Strength, limitations and opportunities associated with SSP approach are critically evaluated to provide directions for the development of new SSPs. Furthermore, the role of capping agents and fundamentals of viable synthetic strategies in general, for materials synthesis and deposition of thin film have been summarised in this account. Finally, the conclusion and future prospects of SSPs have also been included in this review. It is expected that this review will provide library of precursors and optimized conditions to synthesize group IV MCs and further catch the attention of researchers to explore the SSP mediated route in making size- and shape-tunable nanostructures with improved functionalities. [ABSTRACT FROM AUTHOR]

Uniform deposition across large areas of an organic layer is one of the challenges for the industrial application of solution-based organic light‐emitting diode (OLED). In this paper, we propose an organic thin film deposition method for OLED using a micro multi-nozzle jet coating process. The developed micro multi-nozzle jet head consists of eighteen nozzles (100 μm diameter), a side suction line, inlets, and a nozzle protection outer hole. To demonstrate organic thin film deposition for OLED lighting device fabrication, a poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) solution was used as a hole injection layer (HIL). Thickness uniformity of the PEDOT:PSS thin film was analyzed by regulating the jetting pressure. Through single-path coating of twelve successive stable column-jet flows, PEDOT:PSS organic film of 26 mm width was coated on an ITO substrate at 1 m/s head speed. The PEDOT:PSS thin film of 24.25 ± 1.55 nm (CV = 6.39%) thickness was obtained by the proposed coating method. For the feasibility test, OLED lighting devices with emission areas of 20 mm × 20 mm and 70 mm × 70 mm were successfully fabricated using PEDOT:PSS films deposited by a micro multi-nozzle jet coating method. [ABSTRACT FROM AUTHOR]

This study presents a new construction design of a distributed Bragg reflector (DBR) filter and a Fabry–Pérot (FP) filter by using needle technique as a synthesis method. The optimized DBR and FP filters having a proper number of layers with controlling thickness TiO2/SiO2 are utilized to transmit only a certain narrow band of wavelengths while blocking the others. As a proof of concept, the filters are designed to selectively transmit only a very narrow band of wavelength at 780 nm which is the near infrared (NIR) fluorescent emission from Alexa Fluor 750 dye. The obtained results show that the optimized filters represent advanced spectral performance which can be used to improve the sensitivity and the imaging contrast in fluorescence microscopy.

The growth of CZTS thin films by electrodeposition has numerous advantages in terms of controlling the deposition parameters. However, the electrochemical cells in conventional potentiostat are small and require precise adjustment. Electrodeposition is feasible by controlling solely the current without using a reference electrode and hence an expensive potentiostat. The cost and surface area limitations can be overcome by utilizing the simple two-electrodes cell and a current source. Therefore, in this study, CZTS thin films were amperometrically deposited on various substrates using our novel two-electrode electrochemical cell setup. The structural, morphological, compositional, optoelectronic properties of the electrodeposited CZTS thin films have been precisely investigated by adjusting the deposition current. Stoichiometry measurements reveal that the chemical composition and hence crystallinity of thin films strongly depend on the applied current. The critical deposition current for Zn-rich films was found to be between 0.97 and 0.98 mA/cm2. [ABSTRACT FROM AUTHOR]

Deposition of thin film with good thickness uniformity and quality for fabrication of thin film-based dye-sensitized solar cells is a critical factor that determines the reliability and consistency of its photovoltaic performance. In this work, dip-coating method was used for the deposition of ZnO thin films on fluorine-doped tin oxide glass substrates. The structural, electrical and optical properties of these ZnO thin films were characterized by XRD, FESEM, four-point probe, UV–Vis spectroscope and room temperature PL spectroscope. The study showed that the thickness of ZnO thin film could be adjusted by the number of dipping cycles. By increasing the dip-coating cycles, the thickness, crystal quality and absorbance of visible light of ZnO thin films increased whereas the sheet resistance of ZnO thin films decreased. As a consequence, the photovoltaic performance of DSSCs improved with maximum conversion efficiency of 0.68% at 3 cycles of dip coating. Nevertheless, formation of macro-defects such as pores and cracks in thick ZnO thin films became the dominant factor that deteriorated their conversion efficiency down to 0.19% (at 11 cycles). [ABSTRACT FROM AUTHOR]

LixLaySrzMnO3 thin films of various compositions (x,y,z) have been grown using pulsed laser deposition. The compositions of the films have been studied as a function of deposition temperature, target-to-substrate distance and deposition pressure with respect to different cation ratios of the targets by inductively coupled plasma mass spectrometry. When growing multi-elemental oxide thin films containing lithium (with its large mass difference to other elements), lithium loss is most probably inevitable. But the desired thin film composition can be achieved by selecting specific growth conditions and different target compositions. The experiments also elucidate some of the mechanisms behind the incongruent lithium transfer from the targets to thin films. [ABSTRACT FROM AUTHOR]

• A-optimal model-based and factorial DoE are compared for model tuning of CVD system. • Parameter estimates of A-optimal DoE are slightly more accurate than factorial DoE. • A-optimal DoE produces much more accurate prediction of optimal process conditions. • A-optimal and factorial DoE are compared based on trade-off of accuracy and effort. Experimental data is required to estimate unknown parameters for a mathematical model describing thin film growth and to optimize the chemical vapor deposition (CVD) process. The most informative experimental data can be obtained by sequential model-based design of experiments (MBDoE), but this requires significant effort to implement compared to factorial design of experiments (DoE). For CVD processes it is not clear which approach is better or more efficient. Here, we compare the effectiveness of sequential A-optimal (MBDoE) with a factorial (DoE) using a case study involving a mechanistic model of thin-film deposition. The sequential A-optimal MBDoE and factorial DoE are compared based on their effectiveness in obtaining accurate parameter estimates and model predictions. Synthetic experimental data is generated from simulations with the true parameters plus noise. The results suggest that the A-optimal MBDoE is slightly better than factorial DoE for estimating model parameters. The parameter estimates from each experimental design approach are used to solve a model-based optimization problem. The results indicate that model-based optimization from the model with parameter estimates obtained by the A-optimal design gives a significantly better estimate of the optimal process conditions than factorial DoE. [ABSTRACT FROM AUTHOR]

Cadmium sulfide (CdS) was deposited onto a co-polyamide (DHTH) substrate by two different techniques: chemical bath deposition (CBD) and spray pyrolysis (SP). The synthesis of the DHTH resulted from the combination of two bulky pendant groups and a hexafluoroisopropylidene, C(CF3)2, by direct polycondensation. Thermal stability, optical transmittance, and mechanical properties of the DHTH were measured before the CdS deposition. The DHTH substrates exhibited a high transmittance (> 82%) for wavelengths above 400 nm, an elastic modulus of 2.9 GPa, and Tg of 318 °C. CdS was deposited by CBD at 80 °C, using cadmium chloride, potassium hydroxide, ammonium nitrate, and thiourea as chemical reagents. For the SP deposition, cadmium chloride and thiourea were used as chemical reagents while the substrate temperature was fixed to 300 °C. CdS thin films of good transparency and adherence were obtained. The bandgap energy of the deposited CdS films was estimated as 2.32 eV and 2.38 eV, for CBD and SP techniques, respectively. The rms roughness of the CdS was 164 nm for the films grown by CBD and 37 nm for those grown by SP. Finally, the X-ray diffraction confirmed cubic and hexagonal crystalline structures for the CdS grown by CBD and SP, respectively, which agrees with the structures corresponding to low (CBD)- and high (SP)-temperature techniques. The CdS physical properties confirmed the deposition of a semiconducting thin film onto a home-synthesized high-transparency polymer substrate by two different low-cost and scalable techniques, representing an important advancement on the development of new material systems for optoelectronic applications. [ABSTRACT FROM AUTHOR]

Spray pyrolysis deposition of SnCl2.2H2O- and NH4F-containing solution is an appropriate method for deposition of fluorine-doped tin oxide (FTO), which has extensive applications in photovoltaic devices. According to a literature review, several spray preparation methods have been studied. These methods lead to both precipitated and unprecipitated spray solutions. Precipitated and unprecipitated solutions were used for deposition of FTO thin films. FTO obtained from unprecipitated solution yielded the lowest sheet resistance and resistivity, which was due to its highest electron concentration (ne). However, precipitation had no influence on electron mobility. The x-ray diffraction patterns of precipitates showed the presence of Sn- and F-containing compounds, which implied partial depletion of F and Sn from solutions. As a result, a lower amount of F− ions was incorporated into FTO, which led to lower ne. In addition, partial depletion of Sn led to slightly smaller FTO thickness. Finally, FTO thin film deposited from unprecipitated solution gave the highest figure of merit. This means that precipitation in the precursor solution has deleterious effects on electrical and optical properties. [ABSTRACT FROM AUTHOR]

Lithium (Li) doped and undoped NiFe2O4 thin films for supercapacitor application have been prepared through the chemical deposition method. The Li doped and undoped NiFe2O4 thin films for structural, morphological and supercapacitive performance have been studied. As the Li doping percentage varies from 1 at. wt.% to 3 at. wt.%, the thickness of NiFe2O4 thin films increases up to 120 min deposition time, after that slight decrease in thickness was observed. SEM images show randomly grown flake-like structure of Li-NiFe2O4 thin films. The angle of contact of Li-NiFe2O4 thin films decreases with increase in Li doping into NiFe2O4 thin films. The effect of Li doping percentage on supercapacitive performance revealed that as the Li doping percentage is increased from undoped to 3 at. wt.%, the specific capacitance is increased from 314 F/g to 571 F/g. [ABSTRACT FROM AUTHOR]

• Room temperature thermodynamic studies of chemical deposition of Cu2O thin films. • Room temperature chemical bath deposition of Cu2O thin films. • [Cu(T)n]2-n and [Cu(OH)n]2-n in the solution promotes well-defined Cu2O layers. • The pH is the predominant parameter affecting crystal growth size and homogeneity. • Reducing agent, like glucose leads to co-precipitation of metallic Cu at 80 °C. A simple room-temperature chemical bath deposition technique, inspired by the Felhling method, was used to deposit nanocrystalline cuprous oxide (Cu 2 O) thin films. The process involved a mixture of copper sulfate, sodium potassium tartrate, and sodium hydroxide. A thermochemical analysis explored how pH and complexing agent concentration affected Cu(OH) 2 solubility and subsequent Cu 2 O growth using species repartition diagrams. The study is conducted by fixing the [tartrate]/[Cu] ratio at 10, while varying pH, deposition time, and temperatures from room temperature to 80 °C. While oxide nucleation and growth began at pH = 9, denser and more uniform films formed at pH = 10 and 11, corresponding to the co-existing domain of copper hydroxo and copper tartrate complexes. Notably, regardless of pH, temperature, or reducing agent, the Cu 2 O (111) facets appear to be selectively stabilized. The introduction of an aldehyde reducing agent such as glucose had little effect on the growth of Cu 2 O layers at room temperature but promoted the formation of Cu0 at 80 °C. [ABSTRACT FROM AUTHOR]

Gd 0.2 Ce 0.8 O 1.9 /Y 0.16 Zr 0.84 O 1.92 (GDC/YSZ) nanocomposite is synthesized by a novel hybrid chemical route, where colloidal crystalline GDC nanoparticles from continuous hydrothermal synthesis are dispersed into a metalorganic YSZ matrix precursor. The result is a mixture of metal oxides in which GDC nanoparticles are finely distributed in a continuous metalorganic polymeric matrix to be crystallized after calcination. The GDC nanoparticles reduce the temperature necessary to obtain crystalline YSZ, which is already formed at 400 °C. The nanocomposite reveals structural stability up to 800 °C when treated in both air and reducing atmosphere, showing the onset of diffusion below 1000 °C. The diffusional processes are largely dependent on the nanometric grain size, with Zr4+ diffusing abruptly towards GDC in air at 1000 °C and GDC/YSZ interdiffusion being hindered in reducing environment despite the onset temperature of 900 °C. The nanocomposite precursor is an inkjet-printable reactive water-based material, suitable for the deposition of thin films with a thickness below 100 nm after calcination at 750 °C. The crystal structure of the film reveals no interaction between GDC and YSZ but a microstrain (0.3% tensile strain for YSZ). The thin film microstructure shows a compact layer with 94% density. The nanocomposite shows high oxygen ionic conductivity at low temperatures (>5⋅10-3 S⋅cm-1 at 500 °C), low activation energy (0.55 eV), and dominant oxygen ionic conductivity even in reducing conditions (pO 2 < 10–25 atm). We show that these properties arise from the large interface between the components of the composite, due to the embedding of the GDC nanoparticles in the YSZ matrix, while ZrO-CeO intermixing can be avoided and no n-type conductivity is observed even at low oxygen activities and high temperatures. • A novel hybrid synthesis method is adopted for realizing a GDC/YSZ nanocomposite keeping control on the stoichiometry. • Nanometric GDC nanoparticles are uniformly embedded in the matrix, enhancing YSZ formation at low temperature. • The resulting material does not show interdiffusion up to 900 °C. • The GDC/YSZ nanocomposite displays low activation energy for ionic conductivity, higher conductivity than YSZ below 600 °C. • No n-type conduction due to cerium reduction at low pO 2 is observed. [ABSTRACT FROM AUTHOR]

Low-temperature deposition of electroceramic thin films allows the construction of new devices and their integration with existing large-scale fabrication methods. Developing a suitable low-cost deposition method is important to further advance the development of microdevices. In this work, we deposited a 1-μm-thick La0.6Sr0.4CoO3−δ (LSC) perovskite with high electrical conductivity on sapphire substrates at 400°C and analyzed its electrical, morphological and structural properties as a function of temperature in the range of 400–1100°C. The results show that spray pyrolysis can be used to deposit high-quality reproducible layers with the desired chemical and phase composition. Upon heating to around 600°C, the residual C–O and C=O species are removed, and the deposited layers crystallize and become conducting. The dependence of electrical conductivity versus processing temperature has a complex character—the maximum conductivity is found for layers processed at 800°C. An analytical model of stress distribution was used to predict stress to which the bi-layer material would be exposed to while being cooled down from the annealing temperature to room temperature. The high electronic conductivity and high-quality microstructure of the LSC layers, which can be adjusted with the appropriate heat treatment procedure, make them suitable for applications in electrochemical devices applied in integrated energy modules, including electrodes or contacts. [ABSTRACT FROM AUTHOR]

We herein report a thin film deposition of perovskite BaCo 0.4 Fe 0.4 Zr 0.1 Y 0.1 O 3-δ (BCFZY) by pulsed laser depositing (PLD) method for the use as a cathode in solid oxide fuel cells (SOFCs). The BCFZY powder was first synthesized via sol-gel method and pelletized to employ it as a target in PLD system. As a result, the PLD-deposited thin BCFZY film showed nano-porous morphology and preferred nano-architecture for cathode of SOFCs. The applicability of the thin film BCFZY to SOFC cathode was even confirmed by fabricating an SOFC with BCFZY cathode and operating it at 500 °C, where stable open-circuit voltage of 1.13 V was measured for an hour. • BCFZY thin film is deposited as a SOFC cathode by pulsed laser deposition. • PLD deposited BCFZY thin film has no defects and preserves perovskite structure. • BCFZY thin film applied electrolyte support SOFC shows excellent oxygen reduction reaction activity. [ABSTRACT FROM AUTHOR]

Newly synthesized dithiocarbamate precursors of platinum are used in a facile one-step AACVD procedure to fabricate pure phase platinum thin films of deposition time dependent structural and dimensional attributes. These films have shown higher efficiency as counter electrodes in dye sensitized solar cells as compared to the configurations using platinum electrodes made via doctor blade's method. A facile and cost effective AACVD procedure for the synthesis of platinum thin films has been reported using newly synthesized Pt-dialkyldithiocarbamate complexes, [Pt(S 2 CNR 2)] (where R = isobutyl, i Bu (1); benzyl, Bz (2)), as single source precursors. The structural characterization of the dithiocarbamate complexes has been performed by single crystal X-ray diffraction, 1H and 13C NMR, FT-IR and thermogravimetric analysis. The structure, composition, and morphology of the resulting Pt-films is established through XRD, XPS, EDX and FE-SEM analyses. The catalytic performance of the as-synthesized Pt-films is evaluated by using them as counter electrodes in dye sensitized solar cells as an example application. The efficiency of the AACVD produced electrodes is found to be better than conventionally used Pt-counter electrodes made from the doctor blade's method. It is also demonstrated that films having a well-connected and defect free surface topography show better catalytic performance, which is due to their high conductivity and reflectivity. Thus a simple and low cost method employing dithiocarbamate precursors is manifested to be immensely efficient in generating Pt-films and electrodes of tremendous applicability. [ABSTRACT FROM AUTHOR]

Abstract In this work, Vapor Annealing Sintering (VAS) process was introduced for low-cost pressureless producing dense Zinc Oxide (ZnO) thin films deposited from nanoparticles at near-room temperature (50 °C). Spontaneous densification evolution from nanoparticulate to a dense film via a dissolution-diffusion-reprecipitation mechanism was observed exposing ZnO layers to the vapor of an acetic acid aqueous solution at isothermal condition. The influence of the annealing on the optical properties of the treated films was investigated in order to study the structural changes. The proposed method can allow new opportunities for simple and low-cost ceramics thin film manufacturing also involving pressure and temperature-sensitive materials. Graphical abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

Abstract We present the structural, optical properties, and electronic excitation spectra of the YbFe 2 O 4 thin film deposited on (0001) sapphire substrates. The optical spectra of a YbFe 2 O 4 thin film show several electronic transitions, dominated by Fe d to d on-site electronic transitions as well as O 2 p to Fe 3 d , Yb 6 s , and Yb 5 d charge-transfer electronic transitions. The direct energy band gap of YbFe 2 O 4 has been found to be 1.40 ± 0.01 eV at 300 K. Moreover, the electronic transitions centered at 1.75 eV and 2.41 eV exhibit strong temperature dependence with a discontinuity at ∼190 ± 10 K, indicating evidence for a structural instability in the system. The optical spectra of YbFe 2 O 4 have been analyzed and also compared with that of isostructural YFe 2 O 4 and LuFe 2 O 4. Highlights • YbFe 2 O 4 thin films by reactive electron-beam deposition. • Temperature dependence of electronic excitations of YbFe 2 O 4. • Direct energy bandgap of 1.40 eV at 300 K. • Structural instability in YbFe 2 O 4. [ABSTRACT FROM AUTHOR]

The types of thin film deposition techniques and their differences are presented in this article. The characteristics of magnetron sputtering techniques are thoroughly observed. A review of recent research efforts and developments for the fabrication of semiconductor resistive gas sensors using magnetron sputtering deposition methods, presenting its potential advantages as a materials synthesis technique for gas sensors along with a discussion of their sensing performance are also presented. It can be argued that these advantages are likely to drive increased interest in the use of magnetron sputtering techniques for gas sensor materials over the next decade as the advanced physical vapor deposition (PVD) method. [ABSTRACT FROM AUTHOR]

Abstract Mictrostructured silicon oxide (SiO x) thin films were deposited on glass and metal substrates from 1,1,1,3,3,3-hexamethyldisilazane (HMDSN) and hexamethyldisiloxane (HMDSO) by using atmospheric-pressure thermal microplasma jet. Two kinds of string-like products, randomly bent string-like products and linear string-like products, were deposited and they formed microstructured films. The bent string-like products formed labyrinth-like structures and the linear string-like products lay in parallel to form a large aligned structure. The width of both the bent and linear string-like products was from 1 to 3 μm, regardless of the kind of the precursor but depending on the plasma irradiation conditions. The influence of various surface microstructure of substrates on the formation of the SiO x microstructure was investigated to make clear the mechanism for the formation of the microstructures. Highlights • String-like SiO x products were formed by atmospheric pressure thermal microplasma. • Bent string-like products and linear string-like products were formed. • Bent string-like products formed labyrinth-like structures. • Linear string-like products lay in parallel and formed a large aligned structure. • Microscopic plasma gas flow determined the direction of the aligned structure. [ABSTRACT FROM AUTHOR]

The paper deals with the synthesis of palladium-iron alloy thin film with the ordered L10 structure and presents results of its studies. The evolution of the thin film crystallinity is described at different stages of synthesis. Perpendicular magnetocrystalline anisotropy is confirmed by results of magnetometry and Mössbauer spectroscopy. Based on results, it is concluded that the obtained structure can be used as a medium for ultrahigh density magnetic recordings. [ABSTRACT FROM AUTHOR]

Abstract Molybdenum (Mo) thin films are widely used in microelectromechanical systems (MEMS) applications. Mo bilayer deposition by direct current (DC) magnetron sputtering has been proposed in order to attain the desired smooth surface, small in-plane tensile stress and high degree crystallisation of Mo thin film for the fabrication of MEMS actuators and electrodes. The influences of sputtering time (10 min–40 min) and sputtering DC power (100 W–250 W) on the physical and microstructural properties of single layer Mo thin film have been evaluated. The optimised sputtering conditions for bottom and top layer of Mo bilayer have been determined and the individual influence of each layer on the resulting Mo bilayer has been discussed. Our studies reveal that the deposition of top Mo layer with small surface roughness but high in-plane tensile stress has reduced the high surface roughness of bottom Mo layer and simultaneously retained the small in-plane tensile stress. Reducing the sputtering time and/or using similar sputtering power for bottom and top layers improved the crystallinity of Mo bilayer along the preferred 〈110〉 direction. Mo bilayer thin films of total thickness < 1 μm, crystallite size >19 nm, surface roughness <2.5 nm and in-plane tensile stress <500 MPa have been attained. Highlights • Reduce molybdenum (Mo) surface roughness, R a by depositing top Mo layer of smaller R a. • Similar sputtering power for top and bottom layer yields good crystals in Mo bilayer. • Strong association between tensile stress and compressive strain in Mo mono/bilayer. [ABSTRACT FROM AUTHOR]

Abstract Magnetron sputtered thin film metallic glasses (TFMGs) with nanoscale heterogeneities have attracted much interest since they are amorphous materials, whose properties can be tailored. In this work, we investigated the different growth modes observed in magnetron sputtered TFMGs. We sputtered Au-based TFMGs under different working pressures of Ar, ranging from 0.4 to 10 Pa. In addition, the influence of the substrate roughness on the thin film microstructure was studied. Our results show two distinct thin film growth modes: homogeneous at low working pressures and nanostructured with mesoscopic hills and nanocolumns at higher working pressures. We also demonstrate that an increase in substrate roughness promotes the formation of nanostructures such as nanocolumns, even at relatively low working pressures. Our finding shows that the final microstructure of the film originates from a competition of surface diffusivity and shadowing effect. Highlights • Au-based thin film metallic glasses were deposited by DC magnetron sputtering. • Growth mode transition: homogeneous to nanostructured at higher working pressure • Higher substrate roughness shifts transition to lower working pressures. • A competition of shadowing effect and surface diffusivity explains the transition. [ABSTRACT FROM AUTHOR]

Present study investigates the structural and magnetic properties of TiO 2 thin films prepared by electron beam evaporation technique, annealed at 900 °C and irradiated with 500 keV Ar 2+ ions. The films before irradiation exhibit anatase phase. Irradiation leads to diffused XRD peaks indicating amorphisation of the anatase phase at the fluence of 1 × 10 14  ions/cm 2 . Increasing the fluence to 5 × 10 16  ions/cm 2 leads to evolution of brookite phase out of the amorphous TiO 2 . In addition, an impurity phase, Ti 4 O 7 is observed in pristine as well as in irradiated films, which show radiation resistant behavior to 500 keV Ar 2+ ion irradiation upto the highest fluence 5 × 10 16  ions/cm 2 . Anatase to brookite phase transformation followed by an intermediate amorphous phase occurs without showing either grain growth or change in film thickness as evidenced from Atomic Force Microscopy (AFM) and Rutherford’s Back Scattering (RBS) measurements, respectively. Further, both pristine and irradiated films exhibit ferromagnetic behavior at room temperature (RT) irrespective of their phase and crystallinity. The difference in magnetization observed in pristine and film irradiated at ion fluence 5 × 10 16  ions/cm 2 is ascribed to the difference in oxygen vacancies. [ABSTRACT FROM AUTHOR]

A metal-ceramic multilayer composite composed of Zr and ZrC films was magnetron sputter deposited and annealed at 1325 °C to demonstrate its ability to phase transform into a single phase, substoichiometric ultrahigh temperature ceramic carbide. The pre-annealed laminate microstructure comprised columnar grains for both the Zr and ZrC layers, common to thin film deposition. Upon annealing, the diffusion of carbon facilitated the precipitation of multiple equiaxed carbide grains that consumed the former Zr layers. As this carbon diffused from ZrC, it resulted in the carbide undergoing a lattice contraction where the elastic strains facilitated a decohesion between the carbide grain boundaries. This decohesion is shown to be mitigated by increasing the ratio of the initial ZrC layer-to-Zr layer thicknesses. Finally, oxygen, found to be a minor impurity in the ethylene hydrocarbon gas used to reactively deposit ZrC, facilitated irregular zirconia precipitation within the evolving microstructure during the anneal. [ABSTRACT FROM AUTHOR]

The protective coating layer for accident tolerance fuels (ATF) will offer a fuel efficient, enhanced oxidation resistance of zirconium alloy, and safe operation by active cooling of the reactor. The various coating methods on the surface of zirconium alloy such as physical vapor deposition, chemical vapor deposition, and cold spray have been tried to optimize the thin film layer for enhanced ATF performance. Among them, physical vapor deposition is a potential candidate for ATF coating layer due to its low temperature process ensuring mechanical strength of zircaloy cladding during coating process. The silicon carbide (SiC) is promising for extremely high irradiation doses, which provide saturated swelling after a few months of typical operation. As alternative claddings, SiC with various concentration of Si has been deposited on zircaloy cladding for the oxidation resistances. It has been tested at 900 °C for 500 h in steam environment. The enhancement of oxidation resistance of SiC/Si composite coating layer was attributed to an oxidation of Si component to SiO x during steam environments. [ABSTRACT FROM AUTHOR]

In this study, we demonstrate the formation of a peculiar carbon pattern from polyacrylonitrile/poly(methyl methacrylate) (PAN/PMMA) blend thin films under external electric fields. When a spin-coated PAN/PMMA blend thin film was exposed to an electric field, the surface of the thin film facing air layer would fluctuate due to the electrohydrodynamic instability phenomenon induced by an electrostatic force. At the same time, the interface between PAN and PMMA would also become unstable because of the difference in the dielectric constants of PAN and PMMA. The microstructure of the PAN/PMMA thin film obtained after field exposure was influenced by the combined effect of the two phenomena. Subsequent controlled thermal treatment produced an unprecedented and peculiar carbon pattern, which remained intact during carbonization. The effect of experimental parameters such as field intensity, exposure time, and film thickness on the microstructure of the polymer precursor and resulting carbon pattern was investigated. This work provides a strategy to obtain carbon structures showing specific surface texture and certain properties that have been inaccessible by any other means. [ABSTRACT FROM AUTHOR]

Cadmium Selenide (CdSe) and antimony (Sb) incorporated CdSe (CdSe:Sb) thin films were deposited by electron beam evaporation technique at various concentration of Sb (5 wt%, 10 wt%, 15 wt% and 20 wt%). The effect of Sb concentration on the properties of CdSe thin films was investigated. Formation of hexagonal crystal structure with preferred growth along [001] direction was confirmed by X-ray diffraction analysis. The interplanar spacing, lattice constant, average crystallite size, strain and dislocation density of CdSe and CdSe:Sb thin films were calculated from X-ray diffraction studies. The crystallite size of CdSe thin film is 40 nm, which is decreased to ~25 nm with increasing Sb concentration in CdSe from 5 wt% to 20 wt% in the source material. Optical transmittance of the CdSe films obtained from UV–Vis spectra is decreased with various amount of Sb incorporation in CdSe film. Direct optical band gap of the film varies in the range of 1.74–2.3 eV as a function of Sb concentration in the source material. Photoluminescence spectra of CdSe:Sb films show near band edge emission at 605 nm and deep trap related emission band at 743 nm. The intensity of the emission bands varies and shows shifts towards the lower wavelength side with increase in Sb concentration. The electrical resistivity is relatively minimum for CdSe:Sb (5 wt%) and further increase in Sb concentration increases the resistivity of the CdSe films. [ABSTRACT FROM AUTHOR]

Plasma enhanced atomic layer deposition (PE-ALD) of aluminum nitride (AlN) thin films often utilizes NH 3 or a mixture of N 2 and H 2 as a plasma source. However, the possibility of separating the activation step from the nitridation step by using H 2 alone as the plasma source has never been explored. In this paper, we study the deposition of AlN by PE-ALD by using trimethylaluminum, H 2 plasma and NH 3 for deposition temperatures below 400 °C. The self-limiting ALD growth was achieved between 325 °C and 350 °C. As a comparison, AlN was also deposited by thermal ALD (T-ALD), where surface reactions between TMA and NH 3 occurred with reasonable growth rates only at temperatures above 400 °C. The PE-ALD films showed low oxygen (1.5 at.%) and carbon contaminations (1 at.%). The T-ALD films contained carbon (5 at.%) mainly attributed to the presence of C Al bonds that was insignificant in PE-ALD films. The flow rate of H 2 used in H 2 plasma was found to have a significant impact on the preferred orientation of AlN films, where higher H 2 flow rate promoted the (002) preferred orientation. Besides, the electrical resistivities were probed to be 10 8  Ω cm, as expected in an insulating material. As an example, AlN was used to infiltrate porous sintered silicon carbide (SiC). Both AlN deposited by PE-ALD and by T-ALD operating with exposure mode deposited at 400 °C were attempted. Even though, there is a greater risk for TMA precursor to decompose at 400 °C, infiltration of AlN was more successful by T-ALD operating with exposure mode. [ABSTRACT FROM AUTHOR]

In this study, zinc sulfide thin films were deposited on glass substrates at room temperature by vacuum thermal evaporation using oblique angle deposition technique. The samples were prepared at different incident vapor flow angles 0∘, 65∘, and 85∘. The samples were studied using various characterization techniques. The film crystallinity was found very sensitive to the growth angle. Atomic force microscope images of the samples were used to investigate their morphology and surface roughness. The images of samples obtained by the field emission scanning electron microscopy technique showed that the produced samples had columnar structures with columns tilting toward the incident vapor flow direction. Optical constants were calculated by using the data obtained from UV–Vis analysis. [ABSTRACT FROM AUTHOR]

γ -MnS thin film was deposited at 40 °C temperature on glass substrate by Chemical Bath Deposition (CBD) method that has superior advantageous in terms of fast and cheap production. MnS thin film was annealed in nitrogen atmosphere at temperatures 100, 200, 300, 400, 500 °C for an hour. The effect of annealing temperature on structural and optical properties have been investigated. X-ray diffraction (XRD) analysis revealed that gamma-MnS thin film had the phase change and oxidized at 400, 500 °C annealing temperature. The grain size of the annealed film was calculated between 241 and 280 Å as a function of annealing temperature. It was observed that optical transmission values decreased at wavelength of 400–700 nm (visible region) after annealing at temperatures 400 and 500 °C. Increasing annealing temperature induces reduction in energy band gap values from 3.89 eV down to 3.46 eV. Refractive index ( n ) values were calculated by envelope method. Refractive index values at visible region increased from 2.03 to 2.54 with increasing annealing temperature. [ABSTRACT FROM AUTHOR]