Search Results (531)

This study investigated the effects of pH (3, 5, 7, 9, 11) on the structure–activity relationship and stability mechanism of Pickering emulsions stabilized by the gorgon euryale starch–quinoa protein complex. Analyses were performed using reverse compression test, rheology, thermal stability assessment, atomic force microscopy (AFM), and low-field nuclear magnetic resonance (LF-NMR) measurements. Reverse compression test showed that the emulsion at pH 3 exhibited the highest hardness and consistency, but the weakest cohesiveness. Rheological measurements revealed that all emulsions displayed shear-thinning behavior, the emulsion at pH 3 had the highest shear stress and apparent viscosity, while that at pH 11 showed the lowest viscosity due to the destruction of macromolecular structures. Thermal stability assessment indicated that the emulsion at pH 3 did not undergo significant stratification even at 60 °C, whereas the stability of emulsions decreased between pH 5–9. Microscopic analyses (optical microscopy, AFM, and LF-NMR) further confirmed that the emulsion at pH 3 had fine, uniform droplets, strong water-binding capacity, and an interfacial film with a “dense protrusion” structure. This study provides a basis for the environmental adaptability design of functional emulsions and contributes to the high-value utilization of gorgon euryale and quinoa resources. Full article

The motivation for this work is to study the cause and present mitigation for some challenges faced in preparing porous silicon. This enables benefiting from the appealing benefits of porous silicon that offers a wide range, simple technique for varying the refractive index. Such challenges include the refractive index values, sensitivity to oxidation, some fabrication parameters, and other factors. Additionally, highly doped p-type silicon is preferred to form porous silicon, but it causes high losses, which necessitates its detachment. We investigate some possible causes of refractive index change, especially after detaching the fabricated layers from the silicon substrate. Thereby, we could recommend simple but essential precautions during fabrication to avoid such a change. For example, the native oxide formed in the pores has a role in changing the porosity upon following some fabrication sequence. Oppositely, intrinsic stress doesn’t have a significant role. On another aspect, the effect of differing etching/break times on the filter’s responses has been studied, along with other subtle details that may affect the lateral and depth homogeneity, and thereby the process success. Solving such homogeneity issues allowed reaching thick layers not suffering from the gradient index. It is worth highlighting that several approaches have been reported; unlike these, our method doesn’t require sophisticated equipment that might not be available in every lab. To well characterize the thin films, it has been found essential that freestanding monolayers are used for this purpose. From which, the wavelength-dependent refractive index and absorption coefficient have been determined in the near infrared region (1000–2500 nm) for different fabricated conditions. Excellent fitting with the measured interference pattern has been achieved, indicating the accurate parameter extraction, even without any ellipsometry measurements. This also demonstrates the refractive index homogeneity of the fabricated layer, even with a large thickness of over 16 µm. Subsequently, multilayer structures have been fabricated and tested, showing the successful nano-manufacturing methodology. Full article

In this paper, a series of iron thin films were prepared using the direct current magnetron sputtering method at different deposition times. By means of characterization techniques such as X-ray diffraction (XRD), transmission electron microscopy (TEM), atomic force microscopy (AFM), and vibrating sample magnetometer (VSM), the structure, surface morphology, and magnetic properties of the iron thin films prepared at different deposition times were systematically investigated. The XRD results indicate that all the iron thin films exhibit a polycrystalline body-centered cubic structure, with an obvious preferred orientation in the (110) direction. As the deposition time increases, the average grain size of the iron thin films gradually increases. This is mainly because the post-sputtered atoms can provide the energy required for the formation, movement, and growth of the already deposited grains or clusters. When the deposition time is too long, factors such as elastic effects and size constraints will limit the growth of grains and clusters. Therefore, for the thin films deposited after 120 s, the average grain size gradually stabilizes. When the deposition time is short, the thin films usually grow in the form of island-like accumulation. Grains and clusters of uneven sizes accumulate on the substrate, so the roughness gradually increases. This also implies an increase in the density of defects such as internal stress and vacancies within the thin film. As the deposition time increases, the thin films gradually transform to grow in a layered and flat manner, and the grain size gradually stabilizes and becomes relatively uniform. Therefore, the roughness of the thin film samples decreases and tends to be stable. The magnetic property test results show that all the iron thin films exhibit ferromagnetism. The iron thin film prepared at a deposition time of 120 s has the best comprehensive performance, with a saturation magnetization M_s of 1567 emu/cm³, a coercivity of 92 Oe, and a remanence ratio of 0.86. Full article

Curtain deflector coating is a widely employed technique for producing thin, uniform films in numerous industrial applications. The flow dynamics in curtain coating become complex near the corner region due to the interaction of the moving substrate and the falling liquid curtain. In this study, an analytical investigation is conducted for the steady, in-compressible, and creeping flow of a Maxwell fluid, under the Navier slip condition at the substrate. The mathematical model is derived from the conservation of mass and momentum representing the nonlinear system which is solved using the Langlois recursive technique in combination with the inverse method. The inclusion of the Navier slip boundary condition in this research makes it novel and remove the singularity which produce the unstable stresses at a sharp corner due to no slip, but the Navier slip gives a stable solution for the stresses at a sharp corner. The analysis demonstrates that substrate slip significantly reduces tangential stresses and enhances the stability of the coating flow. Residual error analysis is also performed to verify the accuracy and convergence of the analytical solutions. The results provide a deeper understanding of how slip effects can be utilized to improve coating uniformity and optimize the operational performance of curtain deflector coating systems. Full article

Background/Objectives: Wound healing is a complex biological process influenced by inflammation, oxidative stress, and cellular regeneration. Plant-derived bioactive compounds have shown potential to accelerate tissue repair through antioxidant and anti-inflammatory mechanisms. This study aimed to develop and evaluate a Platanus orientalis extract-loaded liposomal formulation for potential wound-healing applications. Methods: Four polar extracts (P1–P4) were prepared using different solvent systems and extraction techniques and were characterized by LC-HRMS to determine their phytochemical profiles. Among the identified constituents, quercetin was consistently detected across all extracts and selected as the reference compound due to its well-known wound-healing activity. Liposomes were prepared via thin-film hydration followed by probe sonication and characterized for particle size, polydispersity index (PDI), zeta potential, encapsulation efficiency, and total drug content. In vitro release, cytotoxicity, and wound-healing assays were subsequently conducted to assess performance. Results: The optimized liposome formulation had a mean particle size of 106.6 ± 5.4 nm, a PDI of 0.11 ± 0.04, and a zeta potential of −14.1 ± 0.5 mV. Environmental scanning electron microscopy (ESEM) confirmed the nanosized spherical morphology and homogeneous vesicle distribution, supporting the successful development of the liposomal delivery system. Encapsulation efficiency and total drug content were determined as 72.25 ± 1.05% and 96.15 ± 0.14%, respectively. In vitro release studies demonstrated a biphasic pattern with an initial burst followed by a sustained release, reaching approximately 75% cumulative quercetin release within 24 h. Physical stability testing confirmed that the optimized liposomal formulation remained physically stable at 5 ± 3 °C for at least 60 days. The optimized formulation showed no cytotoxic effects on CDD-1079Sk fibroblast cells and exhibited significantly enhanced wound closure in vitro. Conclusions: These findings indicate that the liposomal delivery of Platanus orientalis extract provides a biocompatible and sustained-release system that enhances wound-healing efficacy, supporting its potential use in advanced topical therapeutic applications. Full article

Wafer-level thin-film stress measurement is essential for reliable semiconductor fabrication. However, existing techniques present limitations in practice. Interferometry achieves high precision but at a cost that becomes prohibitive for large wafers. Meanwhile laser-scanning systems are more affordable but can only provide sparse data points. This work develops a phase-measuring deflectometry (PMD) system to bridge this gap and deliver a full-field solution for wafer stress mapping. The implementation addresses three key challenges in adapting PMD. First, screen positioning and orientation are refined using an inverse bundle-adjustment approach, which performs multi-parameter optimization without re-optimizing the camera model and simultaneously uses residuals to quantify screen deformation. Second, a backward-propagation ray-tracing framework benchmarks two iterative strategies to resolve the slope-height ambiguity which is a fundamental challenge in PMD caused by the absence of a fixed optical center on the source side. The reprojection constraint strategy is selected for its superior convergence precision. Third, this strategy is integrated with regional wavefront reconstruction based on Hermite interpolation to effectively eliminate edge artifacts. Experimental results demonstrate a peak-to-valley error in the reconstructed topography of 0.48 µm for a spherical mirror with a radius of 500 mm. The practical utility of the system is confirmed through curvature mapping of a 12-inch patterned wafer and further validated by stress measurements on an 8-inch bare wafer, which show less than 5% deviation from industry-standard instrumentation. These results validate the proposed PMD method as an accurate and cost-effective approach for production-scale thin-film stress inspection. Full article

With the discovery of amorphous oxide semiconductors, a new era of electronics opened. Indium gallium zinc oxide (IGZO) overcame the problems of amorphous and poly-silicon by reaching mobilities of ~10 cm²/Vs and demonstrating thin-film transistors (TFTs) are easy to manufacture on transparent and flexible substrates. However, mobilities over 30 cm²/Vs have been difficult to reach and other materials have been introduced. Recently, polycrystalline In₂O₃ has demonstrated breakthroughs in the field. In₂O₃ TFTs have attracted attention because of their high mobility of over 100 cm²/Vs, which has been achieved multiple times, and because of their use in scaled devices with channel lengths down to 10 nm for high integration in back-end-of-the-line (BEOL) applications and others. The present review focuses first on the material properties with the understanding of the bandgap value, the importance of the position of the charge neutrality level (CNL), the doping effect of various atoms (Zr, Ge, Mo, Ti, Sn, or H) on the carrier concentration, the optical properties, the effective mass, and the mobility. We introduce the effects of the non-parabolicity of the conduction band and how to assess them. We also introduce ways to evaluate the CNL position (usually at ~E_C + 0.4 eV). Then, we describe TFTs’ general properties and parameters, like the field effect mobility, the subthreshold swing, the measurements necessary to assess the TFT stability through positive and negative bias temperature stress, and the negative bias illumination stress (NBIS), to finally introduce In₂O₃ TFTs. Then, we will introduce vacuum and non-vacuum processes like spin-coating and liquid metal printing. We will introduce the various dopants and their applications, from mobility and crystal size improvements with H to NBIS improvements with lanthanides. We will also discuss the importance of device engineering, introducing how to choose the passivation layer, the source and drain, the gate insulator, the substrate, but also the possibility of advanced engineering by introducing the use of dual gate and 2 DEG devices on the mobility improvement. Finally, we will introduce the recent breakthroughs where In₂O₃ TFTs are integrated in neuromorphic applications and 3D integration. Full article

The development of non-invasive sensors for individualised plant monitoring has become essential in smart farming to increase crop production. However current approaches are focused on the measurement of soil parameters instead, which cannot provide direct information about plant health. Moreover, equipment used for the direct monitoring of plant health are costly with complex operation, hindering their use by the wider community of farmers. This work reports for the first time the development of a flexible and highly transparent sensor, based on thin conductive PEDOT:PSS/PDMS hybrid films directly deposited onto leaves. The films were fabricated by aerosol deposition and could operate under two different modes. The first mode is used for the determination of plant dryness and concentration of ions. The second mode is used as a triboelectric generator to generate up to 7.2 µW cm⁻² electrical power through the friction of the sensors with a leaf. The device was assembled using a low-cost (GBP < 70) microcontroller incorporating environmental sensors, and an intuitive interface was designed for operation. The final sensor could determine the ionic strength at the millimolar level by means of the impedance of electrodes. This performance allowed the study of differences in ionic content and water availability in tomato leaves during day–night cycles. The high stability of the sensors also allowed the long-term monitoring of plant health. Using this technology, a decrease in the leaf ionic strength due to the lack of electrolytes was observed after watering with deionised water for 2 days. Upon supplementation with fertiliser, the recorded ionic strength and leaf water content were similar to the original values prior to the use of DI water, demonstrating the applicability of the device in the early detection of stress factors that could decrease crop production. Full article

It is well established that solar cells convert solar energy into electrical energy, thereby contributing to environmental sustainability by reducing dependence on fossil fuels. In the present study, thin films composed of different materials were employed with the aim of mitigating efficiency losses in polycrystalline solar cells, which operate at a specific output voltage of 0.5 V. To evaluate the performance of these films, solar irradiation tests were conducted in Ciudad Obregón, Sonora, Mexico, during periods that accounted for both seasonal and diurnal variations in solar irradiance. The experiments were carried out during peak solar hours, a time frame that represents the conditions of highest thermal stress and irradiance intensity and is therefore relevant for analyzing heat-related efficiency losses. The thin films investigated included silver nanoparticles, copper sulfide, potassium permanganate, zinc sulfide, and lead sulfide. An improvement of 0.5% in open circuit voltage gain was achieved, corresponding to a temperature difference of 13.5 °C between the hottest and coolest cells. Notably, the cells that exhibited efficiency enhancement were those incorporating silver nanoparticles and potassium permanganate, with varying deposition times in the chemical bath. Among these, the latter demonstrated superior performance (KMnO₄ performed best). So, the objective of this experimental work was to assess the effect of various thin film coatings on the performance of polycrystalline silicon solar cells under natural sunlight. Full article

Zinc oxide (ZnO) thin films were deposited by radio-frequency reactive magnetron sputtering at a cryogenic substrate temperature of −78 °C to explore a novel low-thermal-budget route for semiconductor growth. Despite the extremely low temperature, X-ray diffraction revealed spontaneous partial crystallization of wurtzite ZnO upon warming to room temperature, driven by strain relaxation and stress coupling at the ZnO/SiO₂ interface. Atomic-force and scanning-electron microscopies confirmed nanoscale hillock and ridge morphologies that correlate with in-plane compressive stress and out-of-plane tensile strain. Spectroscopic ellipsometry, modeled using a general oscillator (GO) mathematical model approach, determined a film thickness of 60.81 nm, surface roughness of 3.75 nm, and a direct optical bandgap of 3.40 eV. Photoluminescence spectra exhibited strong near-band-edge emission modulated with LO-phonon replicas at 300 K, indicating robust exciton–phonon coupling. This study demonstrates that ZnO films grown at cryogenic conditions can undergo substrate-induced self-crystallize upon warming, which eliminates the need for thermal annealing. The introduced cryogenic self-crystallization regime offers a new pathway for depositing crystalline semiconductors on thermally sensitive or flexible substrates where heating is undesirable, enabling future optoelectronic and photonic device fabrication under ultra-low thermal-budget conditions. Full article

With the development of distributed electric propulsion aircraft, researching airborne high-efficiency, high-power-density, high-gain, high-dynamic and low-ripple, low-stress DC-DC that meets aviation standards is an urgent and profoundly challenging task (Research Background). We propose a new topology to implement related applications. The new topology consists of an interleaved switched-inductor unit for a high-gain, low-ripple, and high-dynamic response, and a switched-capacitor unit for secondary boosting and low voltage stress. This study first analyzes in depth the operating principle and electrical characteristics of the proposed topology in different modes, showing that the proposed topology can achieve an extremely high voltage gain while maintaining low voltage stress. Moreover, the proposed topology employs interleaved inverse coupled inductors to eliminate right-half-plane zero (RHPZ). We establish a universal design guideline for coupled inductors by deriving the equivalent inductance equations, and we implement an ultra-lightweight switched-coupled inductor using planar thin-film integrated magnetic technology. We conduct small-signal modeling to verify the loop characteristics and stability of the proposed converter. Finally, the correctness of the theoretical analysis and the advantages of the proposed converter were verified through a 5000 W experimental prototype and comprehensive comparative experiments. Full article

The development of collagen-based composite materials for bone tissue engineering requires a comprehensive understanding of their rheological and structural behavior to ensure processability and functional stability. This study investigates the viscoelastic and morphological properties of nanocomposite slurries composed of hydroxyapatite (HA) nanoparticles dispersed in acetic acid solutions of bovine or fish-derived collagen peptides. Frequency and strain sweep tests revealed solid-like behavior and shear-thinning characteristics consistent with printable bioinks. Both formulations yield stresses between 0.7 and 1.5 kPa, values comparable to those reported for 3D-printable HA composites. Over ten days of aging, fish-based formulations retained higher viscosity and modulus, indicating improved temporal stability relative to bovine-based ones. Drop-casting tests confirmed the formation of homogeneous, highly opalescent films, with surface profilometry showing lower waviness for the fish-derived blend, suggesting enhanced microstructural uniformity. These results demonstrate that acetic acid-mediated collagen–HA interactions generate stable, high-fidelity slurries suitable for additive manufacturing applications. The superior rheological properties of fish collagen formulations highlight the influence of peptide source on network evolution, offering valuable insight for optimizing collagen–ceramic composites in regenerative and biomedical applications. Full article

To enhance the electrical performance of MgZnO-TFTs, this study employed radio-frequency (RF) magnetron sputtering to fabricate MgZnO/ZTO thin films. Using these films as the channel layer, bottom-gate top-contact MgZnO/ZTO-TFT devices were constructed. The thin films were characterized using atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). After optimization, the MgZnO/ZTO-TFT exhibited a high field-effect mobility of 16.80 cm²·V⁻¹·s⁻¹, high Ion/off of 7.63 × 10⁸, threshold voltage of −1.60 V, and subthreshold swing as low as 0.74 V·dec⁻¹. Bias stress stability tests were conducted under positive bias stress (PBS) and negative bias stress (NBS) conditions with a source-drain voltage of 20 V and gate bias stresses (VGS) of +10 V and −10 V, respectively, for a duration of 1000 s. The resulting threshold voltage shifts were only +0.58 V and −0.15 V, respectively, indicating excellent bias stability. These results suggest that the ZTO film, serving as the lower channel layer, effectively enhances carrier transport at the MgZnO/ZTO interface, thereby improving the field-effect mobility and on/off current ratio. Meanwhile, the MgZnO film as the upper channel layer adjusts the device’s threshold voltage and enhances its bias stability. Full article

Thin films have become indispensable in shaping the landscape of modern and future technologies, offering versatile platforms where properties can be engineered at the atomic to microscale to deliver performance unattainable with bulk materials. Historically evolving from protective coatings and optical layers, the field has advanced into a highly interdisciplinary domain that underpins innovations in microelectronics, energy harvesting, optoelectronics, sensing, and biomedical devices. In this review, a structured approach has been adopted to consolidate the fundamentals of thin film growth and the governing principles of nucleation, surface dynamics, and interface interactions, followed by an in-depth comparison of deposition strategies such as physical vapor deposition, chemical vapor deposition, atomic layer deposition (ALD), and novel solution-based techniques, highlighting their scalability, precision, and application relevance. By critically evaluating experimental studies and technological implementations, this review identifies key findings linking microstructural evolution to device performance, while also addressing the pressing challenges of stability, degradation pathways, and reliability under operational stresses. The synthesis of evidence points to the transformative role of advanced deposition controls, in situ monitoring, and emerging AI-driven optimization in overcoming current bottlenecks. Ultimately, this work concludes that thin film technologies are poised to drive the next generation of sustainable, intelligent, and multifunctional devices, with emerging frontiers such as hybrid heterostructures, quantum materials, and bio-integrated systems charting the future roadmap. Full article

A common method to examine the reliability of thin films and small volumes of irradiated materials being used in aerospace, energy, and protective coating applications is biaxial straining. With such tests, the fracture and deformation mechanisms occurring under multi-axial stress states can be investigated, which can strongly differ from the simpler uniaxial one. However, devices that can apply a precise and synchronously applied biaxial strain tend to be too large for foils or thin films and do not allow for additional observation methods to be applied to examine film fracture or deformation during the test. A prototype device that can apply synchronous equi-biaxial and semi-biaxial strains and can be combined with multiple in situ methods is introduced. The device is light and compact in design, which allows it to be mounted on optical light microscopes, atomic force microscopes, inside scanning electron microscopes, and even on X-ray beamlines for reflection or transmission measurements. Additionally, digital image correlation was utilized in two geometries to measure strains on a local or global level. The possible errors associated with the device and experiments on polyimide foils and a 100 nm tungsten film on polyimide are presented. Full article