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Silicon carbide (SiC) is one of the superior materials used in the manufacture of electronic components designed to work at high temperatures, high frequencies and high-power. In the past two decades, the application of SiC materials has been expanding as a result of much improved production and processing techniques. Although most SiC chips are still mainly made from 6 inch (1 inch =25. 4 mm) wafers, leading manufacturers have begun developing next-generation parts and chips based upon 8 inch SiC wafers. This study collaborates with leading enterprises in the upstream and downstream of the domestic silicon carbide industry chain in order to facilitate domestic production of 8 inch SiC chips, with the focus being wafer preparation and epitaxial growth. In this work, 8 inch conductive 4H-SiC substrate wafer was prepared by diameter expansion growth, with low average base plane dislocation (BPD) density (251 cm-2) and virtually 'zero threading screw dislocation (TSD)' density (< 1 cm-2) that meet the production requirements. Based on these 8 inch substrates, we achieve fast epitaxial growth (68. 66 μm/h) with domestically produced 8 inch epitaxy equipment and processing packages. The thickness uniformity of the resultant wafers is 0. 89% and the doping uniformity is 2. 05%. These parameters, as well as the defect density, are on par with those of high-quality 6-inch wafers, fully meeting production requirements. The 8 inch wafers prepared in this paper are better than those described in international publications in terms of thickness and doping uniformity. The defect density is only 1/4 of international data. In this paper, multi-wafer repetative text was designed and executed, to verify the stability of 8 inch epitaxy. [ABSTRACT FROM AUTHOR]

Modules based on c-Si cells account for more than 90% of the photovoltaic capacity installed worldwide, which is why the analysis in this paper focusses on this cell type. This study provides an overview of the current state of silicon-based photovoltaic technology, the direction of further development and some market trends to help interested stakeholders make decisions about investing in PV technologies, and it can be an excellent incentive for young scientists interested in this field to find a narrower field of research. This analysis covers all process steps, from the production of metallurgical silicon from raw material quartz to the production of cells and modules, and it includes technical, economic and environmental aspects. The economic aspect calls for more economical production. The ecological aspect looks for ways to minimise the negative impact of cell production on the environment by reducing emissions and using environmentally friendly materials. The technical aspect refers to the state of development of production technologies that contribute to achieving the goals of the economic, environmental and sustainability-related aspects. This involves ways to reduce energy consumption in all process steps, cutting ingots into wafers with the smallest possible cutting width (less material waste), producing thin cells with the greatest possible dimensional accuracy, using cheaper materials and more efficient production. An extremely important goal is to achieve the highest possible efficiency of PV cells, which is achieved by reducing cell losses (optical, electrical, degradation). New technologies in this context are Tunnel Oxide Passivated Contact (TOPcon), Interdigitated Back Contact Cells (IBCs), Heterojunction Cells (HJTs), Passivated Emitter Rear Totally Diffused cells (PERTs), silicon heterojunction cells (SHJs), Multi-Bush, High-Density Cell Interconnection, Shingled Cells, Split Cells, Bifacial Cells and others. The trend is also to increase the cell size and thus increase the output power of the module but also to reduce the weight of the module per kW of power. Research is also focused to maximise the service life of PV cells and minimise the degradation of their operating properties over time. The influence of shade and the increase in cell temperature on the operating properties should preferably be minimised. In this context, half-cut and third-cut cell technology, covering the cell surface with a layer that reduces soiling and doping with gallium instead of boron are newer technologies that are being applied. All of this leads to greater sustainability in PV technology, and solar energy becomes more affordable and necessary in the transition to a "green" economy. [ABSTRACT FROM AUTHOR]

Wafers (wafer-feed) are an effective processing technology and are expected to maintain the continuous availability of animal feed during the dry season. The purpose of this study was to determine the best type of adhesive on the physical quality of sugarcane tops and Tithonia based wafers. This study used the Split Split Plot Design (SSPD). The main plot as factor A was the type of adhesive, consisting of: Tapioca flour (A1), Pathi flour (A2), Gaplek flour (A3), Karagenan flour (A4), palm sugar (A5). The subplots as Factor B are temperature which consists of: 100℃ (B1), 110℃ (B2), and 120℃ (B3), while the sub-plots as factor C are oven time consisting of: 10 minutes (C1), 15 minutes (C2), and 20 minutes (C3). The forage used was Sugarcane tops (Saccharum officinarum) and Tithonia (Tithonia diversifolia) in the ratio of 60:40. The best adhesive in making sugarcane tops and Tithonia based wafers is tapiovca flour with a temperature of 120℃ for 20 minutes, with physical properties such as colour, aroma, and excellent texture with a range (3.73, 3.70, and 3.63), density with a value of 5.68 g/cm3, and water binding capacity with a value of 104.22%. From the research it can be concluded that there are interactions on the physical properties of wafers (colour, aroma, and smell), density and water binding capacity. For further research, the best wafers obtained were continued to the in vitro digestibility stage to see the digestibility of wafers as ruminant feed. [ABSTRACT FROM AUTHOR]

The adoption of three-dimensional (3D) imaging technologies in orthognathic surgery led to the development of virtual surgical planning and printing of patient-specific orthognathic surgical splints (OSSs). The accuracy and precision of 3D printed OSSs are considered important; however, there is limited data in the literature regarding whether the type of resin materials may influence these measures. A virtual OSS was created using a set of typodont models and printed in Biomed Clear, Dental LT V2, and Surgical Guide resins (Formlabs, Somerville, MA, USA), using a stereolithography printer. The upper intercanine width, intermolar width, and arch length were analysed. Differences between the reference dimensions of the virtual splint and the corresponding mean measurements of the 3D-printed splints were mostly considered clinically acceptable. The greatest variation was observed in the arch length for all 3 materials, which relates to the Z-axis of the printer; only 33.3–66.7% of OSSs were within the tolerance limit of ±0.1 mm quoted by the manufacturer. The Surgical Guide group demonstrated the highest degree of accuracy and precision overall. Further research would help to assess the 3D accuracy and precision, explore the variation found between different resin materials used, and confirm the findings of this research. [ABSTRACT FROM AUTHOR]

With the development of the electronics industry, the requirements for chips are getting higher and higher, and thinner and thinner wafers are needed to meet the processing of chips. In this study, a model of the adhesion state of semiconductor wafers in the stacking–clamping process based on microarray adsorption was established, the composition adhesion was discussed, the microarrays of different materials and pressures were experimentally studied, and a molecular dynamics model was established. The molecular dynamics analysis showed that the adhesion force was only related to the type of atom, and the applied pressure did not change the adhesion force. According to the simulation results, the tangential adhesion between the metal and the wafer is greater than that between the ceramic and the wafer, the adsorption force between the aluminum–magnesium alloy and the silicon wafer is shown in the normal direction, and the repulsion force between other materials and the silicon wafer is shown in the normal direction. During the pressure process, the metal is in the elastic deformation stage between the metal and the wafer, the wafer is plastically deformed in the silicon carbide ceramic and wafer, and the wafer is elastically deformed in the alumina ceramic and wafer. In this paper, the adhesion between the substrate and the wafer is studied, a method of constructing microarrays to enhance adhesion is proposed, and the tangential deformation of the array unit under pressure is studied, which provides theoretical support for increasing the adhesion by constructing microarrays. [ABSTRACT FROM AUTHOR]

Biscuits are a popular and desirable snack food by consumers. Still, the quality of these products decreases during the storage process, so this study focuses on improving the wafer's quality and nutritional value and reducing their fragility by partially replacing wheat flour with soybean flour in the following proportions: 5% (T1), 10% (T2), 15% (T3), 20% (T4), and adding ammonium carbonate in different quantities. The sensory evaluation showed that the best wafer treatment was supported with 15% soy flour and 150 g of ammonium carbonate. At the same time, the mean for sensory evaluation is 8.80. Also, the results of the chemical analysis (protein, moisture, fat, carbohydrate, ash, fibre) texture and colour after direct manufacturing and after three months of storage. The result showed a significant increase in the percentage of protein and fat from 6.56±0.30 to 12.19 ± 0.35, 11.56±0.10 to 19.64±0.55, respectively the moisture content was higher in the control was 3.88±0.02 for wafer sample 2.47±0.13, while fibre was 1.93±0.15. The carbohydrates in the control sample were higher than in other treatments. Texture and colour were improved compared with the control. Commercial-batter biscuits with high nutritional value content and high-quality properties can be prepared by replacing wheat flour with 15% soy flour and adding 150 g of ammonium carbonate.

CMOS image sensor (CIS) semiconductor products are integral to mobile phones and photographic devices, necessitating ongoing enhancements in efficiency and quality for superior photographic outcomes. The presence of white pixels serves as a crucial metric for assessing CIS product performance, primarily arising from metal impurity contamination during the wafer production process or from defects introduced by the grinding blade process. While immediately addressing metal impurity contamination during production presents challenges, refining the handling of defects attributed to grinding blade processing can notably mitigate white pixel issues in CIS products. This study zeroes in on silicon wafer manufacturers in Taiwan, analyzing white pixel defects reported by customers and leveraging machine learning to pinpoint and predict key factors leading to white pixel defects from grinding blade operations. Such pioneering practical studies are rare. The findings reveal that the classification and regression tree (CART) and random forest (RF) models deliver the most accurate predictions (95.18%) of white pixel defects caused by grinding blade operations in a default parameter setting. The analysis further elucidates critical factors like grinding load and torque, vital for the genesis of white pixel defects. The insights garnered from this study aim to arm operators with proactive measures to diminish the potential for customer complaints. [ABSTRACT FROM AUTHOR]

Systemic drug delivery is the current clinically preferred route for cancer therapy. However, challenges associated with tumor localization and off-tumor toxic effects limit the clinical effectiveness of this route. Locoregional drug delivery is an emerging viable alternative to systemic therapies. With the improvement in real-time imaging technologies and tools for direct access to tumor lesions, the clinical applicability of locoregional drug delivery is becoming more prominent. Theoretically, locoregional treatments can bypass challenges faced by systemic drug delivery. Preclinically, locoregional delivery of drugs has demonstrated enhanced therapeutic efficacy with limited off-target effects while still yielding an abscopal effect. Clinically, an array of locoregional strategies is under investigation for the delivery of drugs ranging in target and size. Locoregional tumor treatment strategies can be classified into two main categories: 1) direct drug infusion via injection or implanted port and 2) extended drug elution via injected or implanted depot. The number of studies investigating locoregional drug delivery strategies for cancer treatment is rising exponentially, in both preclinical and clinical settings, with some approaches approved for clinical use. Here, we highlight key preclinical advances and the clinical relevance of such locoregional delivery strategies in the treatment of cancer. Furthermore, we critically analyze 949 clinical trials involving locoregional drug delivery and discuss emerging trends. [Display omitted] • Locoregional delivery is an effective alternative to systemic delivery for oncotherapy. • Locoregional delivery can be achieved via direct infusion or depot-based strategies. • Preclinical studies indicate strong abscopal potential of locoregional delivery. • Clinical trials investigating locoregional delivery are increasing exponentially. • Procedure standardization and combination strategy may be fruitful in near future. [ABSTRACT FROM AUTHOR]

As semiconductor processing technologies continue to advance, semiconductor wafers are becoming more densely packed and intricate, resulting in a higher incidence of surface imperfections. Therefore, it is crucial to detect these defects early and accurately classify them to pinpoint the root causes of the defects in the manufacturing process, ultimately leading to improved yield. Therefore, defect detection is critical in the industrial production of monocrystalline silicon. This study employs deep learning techniques to propose a framework for detecting defects on silicon wafers, focusing on optimizing the hyperparameters of support vector machines (SVM). Three methods were utilized to fine-tune the SVM parameters: Bayesian optimization, grid search, and random search techniques. This study demonstrates how selecting optimal values for SVM parameters can lead to better classification. Additionally, real manufacturing data were utilized to evaluate the performance of the proposed SVM classifier, with a comparison to state-of-the-art techniques in the field. By using deep features from ResNet 101 and a support vector machine, this work achieves 74.5% accuracy in identifying wafer defects without employing any optimization technique. However, the performance of the model was further improved by utilizing the random search optimization technique, which yielded the best result among the three optimization techniques tested, with an accuracy of 88.1%. [ABSTRACT FROM AUTHOR]

Scanning electron microscope, atomic force microscope and other equipment play an important role in the fields of topography restoration and detection. However, these devices are generally used in nanometer-scale measurement scenarios. For wafer topography quality control scenarios ranging from microns to hundreds of microns, these technologies have problems such as high cost and slow detection speed. Therefore, developing new, low-cost, and high-precision methods is necessary. To address this problem, a wafer surface reconstruction framework is proposed based on the shape-from-focus principle. In view of the characteristics of the large area and micro-small height of the wafer, to solve the limitations of the existing shape from focus framework, which is generally based on a single field, we created a multi-field image sequence rapid acquisition system and proposed the use of pulse control methods to achieve rapid acquisition of large area images. On the other hand, this paper proposes a dual filtering framework combining the Levy flight filtering principle with the SOR algorithm in point cloud filtering to achieve a balance between smoothing the depth map and maintaining the detailed structure, reducing the impact of noise, and improving the morphology restoration accuracy. To avoid splicing seams between fields, the progressive detection multifield stitching technique is used to complete large-area depth data stitching. Experiments were conducted on both synthetic and real objects to verify the effectiveness of the proposed method. In terms of synthesized images, the accuracy of the three methods significantly improved after applying the proposed method framework. After applying the Tenenbaum method framework, its correlation and peak signal-to-noise ratio improved by 7.5% and 38.2%, respectively, and its root mean square error was reduced by 40.7%. The excellent accuracy reconstruction results of the proposed method was verified through accuracy evaluation experiments. The height errors of the three methods used were all higher than $1~\mu \text{m}$ . However, after using the proposed method framework, the maximum error was only $0.24~\mu \text{m}$ . The experimental results indicated that this method overcomes the area limitation of traditional SFF and is suitable for applying wafer surface morphology measurements.

We discuss a technique for investigating changes in complex topography and shape of structures using geomorphometric methods to study surfaces of wafers and membranes formed by the Bosch process. The wafers were analyzed before and after the deposition of the SiO2 layer. The membranes were analyzed during the bulge testing. The study was carried out using maps of the catchment area and principal curvatures taking into account artifacts of the approximation of experimental data. We found a correspondence between the distribution of lines connecting the highest surface areas before and after the deposition of the SiO2 layer on the wafers. For membranes with structure: Al(0.8 μm)/SiO2(0.6 μm)/Al(1.1 μm), pSi*(0.8 μm)/SiNx (0.13 μm)/SiO2, Al(0.6 μm) we also found that features of membrane boundaries are mainly caused by their initial shape rather than change under the action of an applied pressure. The advantages of geomorphometric methods for studying changes in the shape of wafers and thin-film membranes in technological processes for the manufacturing of microelectronic devices are shown in comparison with traditional methods for analyzing surface topography maps. [ABSTRACT FROM AUTHOR]

Synchrotron X-ray rocking curve imaging (RCI) is modified to visualize local bending of lattice planes of a single crystal substrate (XR-V-LBLP). This method uses two-azimuth RCI datasets of asymmetric reflection or symmetric reflection. The analysis algorithm is described and a Python software code is provided in the Supplementary material. The two symmetrically equivalent $$11\bar 24$$ datasets obtained from a GaN (0001) 4-inch wafer are reanalyzed using this software. The normal vector, reciprocal-lattice vector, of the local lattice planes, which is approximately parallel to the sample surface, is formulated as the product of two rotation matrices. This vector is written in polar coordinates using the length and two declination angles, newly introduced in this article. The spatial and probability distributions of the declination angles are also presented. The proposed method enables visualization of the local shape or orientation of the lattice planes of the entire wafer. The limits of application of the method are examined for the samples studied. The sample is found to satisfy two conditions regarding the relative $$d$$-spacing difference and the curvature of the lattice planes at all 50 adjacent μm positions.

Phase-calculation formula, involving a window and Fourier transform term, have been used for decades to profile the shape of sample surfaces. Windows can be designed using the phase-calculation polynomial theory to eliminate various types of phase errors. Here, we discuss the phase errors calculated by the phase-calculation formulas, comprising the windows and Fourier transform terms, by considering not only the linear error of the phase modulation but also the combined error between the higher harmonics and linear error of the phase modulation. The surface topography of a 4-inch wafer was also profiled using phase-calculation formulas for the various types of windows and a Fizeau-type interferometer. We also discuss the repeatability of the phase errors calculated using phase-calculation formulas. [ABSTRACT FROM AUTHOR]

With the development of the electronics industry, the requirements for chips are getting higher and higher, and thinner and thinner wafers are needed to meet the processing of chips. In this study, a model of the adhesion state of semiconductor wafers in the stacking–clamping process based on microarray adsorption was established, the composition adhesion was discussed, the microarrays of different materials and pressures were experimentally studied, and a molecular dynamics model was established. The molecular dynamics analysis showed that the adhesion force was only related to the type of atom, and the applied pressure did not change the adhesion force. According to the simulation results, the tangential adhesion between the metal and the wafer is greater than that between the ceramic and the wafer, the adsorption force between the aluminum–magnesium alloy and the silicon wafer is shown in the normal direction, and the repulsion force between other materials and the silicon wafer is shown in the normal direction. During the pressure process, the metal is in the elastic deformation stage between the metal and the wafer, the wafer is plastically deformed in the silicon carbide ceramic and wafer, and the wafer is elastically deformed in the alumina ceramic and wafer. In this paper, the adhesion between the substrate and the wafer is studied, a method of constructing microarrays to enhance adhesion is proposed, and the tangential deformation of the array unit under pressure is studied, which provides theoretical support for increasing the adhesion by constructing microarrays.

CMOS image sensor (CIS) semiconductor products are integral to mobile phones and photographic devices, necessitating ongoing enhancements in efficiency and quality for superior photographic outcomes. The presence of white pixels serves as a crucial metric for assessing CIS product performance, primarily arising from metal impurity contamination during the wafer production process or from defects introduced by the grinding blade process. While immediately addressing metal impurity contamination during production presents challenges, refining the handling of defects attributed to grinding blade processing can notably mitigate white pixel issues in CIS products. This study zeroes in on silicon wafer manufacturers in Taiwan, analyzing white pixel defects reported by customers and leveraging machine learning to pinpoint and predict key factors leading to white pixel defects from grinding blade operations. Such pioneering practical studies are rare. The findings reveal that the classification and regression tree (CART) and random forest (RF) models deliver the most accurate predictions (95.18%) of white pixel defects caused by grinding blade operations in a default parameter setting. The analysis further elucidates critical factors like grinding load and torque, vital for the genesis of white pixel defects. The insights garnered from this study aim to arm operators with proactive measures to diminish the potential for customer complaints.

In semiconductor wafer manufacturing process, the height of random defects provides an important physical parameter to understand their impact and root cause. In this work, we demonstrate a novel method of defect height estimation based on SEM images without using ground truth or any external reference data of target defect types. Our method is applicable in conditions such as absence of shadows, self-obstruction by defects, lack of precise knowledge of SEM detector geometry and does not require sample tilting or imaging at different working distances, thereby removing major limitations of previous work. The error in our height estimation is $\sim 3$ % compared with $\sim 11$ % for current manual method on same dataset. In addition to improving accuracy and precision, our method reduces the time and manual effort required and can be easily extended to past and new defects for trend monitoring purpose, thus satisfying some key requirements of manufacturing environment. [ABSTRACT FROM AUTHOR]

Purpose: Fluid mud is highly disturbed during contaminated sediment capping when the settling velocity of the capping material is excessive. This study investigated how to reduce this disturbance in order to achieve better control efficiency. Materials and methods: Spherical, cubical, wafer-shaped, and sand materials were used as capping materials. The settling velocity, change in landing kinetic energy, and stable capping effect of the materials were studied through settling velocity, capping, and disturbance experiments. Results and discussion: Compared to other capping materials, the use of wafer-shaped materials significantly reduced the turbidity (expressed in nephelometric turbidity units (NTU)) and total phosphorus (TP) concentration in the overlying water after capping under both static and dynamic disturbance conditions. Conclusions: The results indicated that shaping capping materials into a wafer could effectively reduce the settling velocity and landing kinetic energy to reduce the disturbance of fluid mud during capping and achieve better control efficiency. [ABSTRACT FROM AUTHOR]

Abstract Candidiasis is one of the most common fungal infections of oral cavity in humans, causing great oral discomfort, pain and aversion to food. To develop more effective antifungal systems for the treatment of oral candidiasis, an oral mucoadhesive wafer containing sertaconazole solid dispersion (STZ-SD) was developed in this study. Dispersion of STZ in Soluplus® as a solubility enhancement excipient was done by melting, solvent evaporation and freeze drying method at various STZ to Soluplus® ratios. The optimized STZ-SD was then incorporated in the sodium carboxymethyl cellulose (SCMC) gel, xanthan gum gel, or their combination to prepare the lyophilized wafers. The swelling capacity, porosity, and mechanical, release and mucoadhesive properties of the wafers, together with their antifungal activity, were then evaluated. The melting method sample with the ratio of 8:1 showed the best results in terms of saturation solubility and dissolution rate. The STZ-SD-composite wafer exhibited higher hardness and mucoadhesion, as compared to those made of the SCMC polymer. The STZ-SD-wafer also exhibited a greater antifungal effect when compared to the STZ-wafer. The present study, thus, suggested that the STZ-SD-wafer could serve as a novel effective delivery system for oral candidiasis treatment.

The requirements for the surface quality of monocrystal SiC wafers as the representatives of third-generation semiconductors have been raised to a sub-nanometer/nanometer scale (SN/N scale), i.e., few tenths of nanometer to few nanometers. To meet wafer processing needs at these scales, it is essential to understand microscopic wear behavior and material deformation mechanism between the abrasive and the SiC substrate. Large-scale molecular dynamics simulation technology has the unique advantages in the analysis of microscopic interactions. In this paper, a series of wear behaviors and material removal mechanisms in rotary motion machining processes are analyzed for three types of available commercially 6H-SiC crystals with different off-axis angles (0°, 4°, and 8°). The relationship between the micro-friction coefficients and processing parameters (off-axis angle, cutting distance, and depth of cut) is studied. At the same time, slip deformation mechanism, abrasive wear behavior, and maximum subsurface damage depth of 6H-SiC are analyzed in detail. The results of the current work are of great significance for understanding the interaction mechanisms between diamond abrasives and SiC wafers under SN/N scale conditions. [ABSTRACT FROM AUTHOR]

Copyright of Current Social & Economic Processes / Jelenkori Társadalmi és Gazdasági Folyamatok is the property of University of Szeged, Faculty of Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The use of metal halides promotes the development of X‐ray detectors (XDs) owing to their excellent X‐ray absorbance, electrically benign defects, and large mobility−lifetime (µτ) product. Yet the severe baseline drift, size limitation, large dark current, and mediocre stability are still waiting to be solved. Herein, high density size‐scalable Cs4PbBr6 wafer‐based XD is constructed by the hot isostatic‐pressed method for the first time. Meanwhile, different Br− vacancy (VBr) concentration‐based Cs4PbBr6 is realized. The role of VBr in electrical structure and charge transport is highlighted by density functional theory and experimental measurement. Moreover, the further study points the 0D structure endows Cs4PbBr6 with high activation energy for ionic transport (1044 meV) and bandgap (3.88 eV), which finally results in an ultra‐stable baseline and thermal stability. On the basis of efficient response (7068 µC Gyair−1 cm−2), reliable current output, ultra‐low detection limit (1.75 nGyair s−1), high spatial resolution (5.2 lp mm−1 at modulation transfer function = 0.2), fast response speed and radiation stabilities (>1000 Gyair), the high‐resolution X‐ray images under broad energy range (20–160 keV) are realized on both single‐pixel and linear scanning mode, thus holding huge potential for medical diagnosis, safety inspection, and outer space detection. [ABSTRACT FROM AUTHOR]

Curcumin is the main active constituent in turmeric, and it is one of the biopolyphenolic compounds. A cumulative body of research supports the use of curcumin in the treatment of wounds, yet poor water solubility and lack of therapeutic dose determination hamper its use for this therapeutic purpose. This work aimed at preparing novel curcumin wafer dressings to provide a favorable environment for wound healing. Hybrid synthetic (PVA, PVP, HPMC, and CMC) and biodegradable (sodium alginate and dextran) polymers were employed to prepare wafer dressings loaded with incremental three doses (2, 10, and 20 mg) of curcumin per a wafer dressing. The solvent casting method was used to prepare the dressings. Dimension, surface pH, mechanical properties, DSC, FTIR, XRD, erosion time, and in vitro release were studied. Skin wound healing assay was studied in Wistar albino rats. Six curcumin-loaded wafers were successfully prepared with good mechanical properties. Curcumin was dispersed in an amorphous/molecular form, as evidenced by thermal (DSC) and spectral (FTIR and XRD) analyses. Prolonged curcumin release (>24 h) was recorded for F6 (10 mg curcumin) and F7 (20 mg curcumin). Wound healing rate constants and time for 50% wound closure (T1/2) were estimated from a semi-log wound diameter versus time curve. A superior healing rate (up to 3-fold faster) was recorded for curcumin-loaded wafer dressings containing 10 mg (F6) with T1/2 of 7 days compared to 20 days for the placebo-treated group. These results warrant using the selected curcumin-loaded wafer dressing for safer and faster wound closure. [ABSTRACT FROM AUTHOR]

This study aims to design and characterize berberine-loaded wafers for the treatment of chemotherapy-induced oral mucositis. Wafers were prepared by lyophilization of hydrogels of various ratios of chitosan (CS)/sodium alginate (SA) as well as CS/hydroxypropyl methylcellulose (HPMC). In vitro release, in vitro mucoadhesion, porosity, and swelling studies were conducted to select the optimized formulations. Moreover, scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and mechanical properties studies were also performed for further characterization. The efficacy of optimized berberine-loaded wafers in the treatment of oral mucositis was investigated in a 5FU-induced oral mucositis rat model. F2-CS-SA and F6-CS-HPMC wafers exhibited sustained release profile and excellent mucoadhesion strength. Therefore, these wafers were selected as the optimized formulations. SEM confirmed the porous structure of these wafers and is in agreement with the results of porosity and swelling studies. XRD and FTIR studies indicated that berberine was incorporated into the wafer matrix in the amorphous form. In vivo studies demonstrated that topical application of berberine-loaded optimized wafers reduced significantly the severity of 5FU-induced oral mucositis and decreased the expression of inflammatory markers (TNF-α and IL-1β). The results of in vitro and in vivo studies revealed that berberine-loaded F2-CS-SA and F6-CS-HPMC wafers can be effective in the treatment of chemotherapy-related oral mucositis. [ABSTRACT FROM AUTHOR]

Reducing the self-heating of SiC- and GaN/SiC-based high-powered devices by integrating diamond films offers promising performance enhancement of these devices. However, such a reduction strategy faces serious problems, such as diamond nucleation on SiC and stress accumulation greater than 10 GPa. In this work, a SiN x dielectric layer (∼50 nm) was coated onto the C polar face of a 4H–SiC wafer using microwave plasma chemical vapor deposition (MPCVD) to improve direct dense diamond nucleation and growth, significantly reduce the stress, and build Si–C(SiC)⋯Si⋯C(diamond) bond bridges. This SiN x thin layer, prepared by activating Si ions under Ar/N plasma during magnetron sputtering, gave rise to local Si 3 N 4 crystal features and a low effective work function (EWF) for promoting surface dipoles with electronegative carbon-containing groups. In the H plasma environment during diamond growth, the local Si 3 N 4 crystal was amorphized, and the N atoms escaped as a result of atomic H and the high temperature. At the same time, C atoms diffused into the SiN x and formed C–Si bonds (49.7% of the total C bonds) by replacing N–Si and Si–Si, thus increasing the direct nucleation density of the diamond grains. The diamond thin film grew rapidly and uniformly, with a grain size of approximately 2 μm in mixed orientation, and the stress of the 2-inch SiC-on-diamond wafer was extremely low (to ∼0.1–0.2 GPa). In comparison, partially connected diamond grains (>10 μm) on the bare SiC in the preferential (110) orientation resulted in a film with twin-grain features and significant stress, which was associated with the hexagonal lattice interface of 4H–SiC. These results are considered the material and surface/interface bases for actively controlling wafer fabrication and enhancing the heat dissipation of SiC and GaN/SiC electronics. [ABSTRACT FROM AUTHOR]

Indium antimonide (InSb) materials have been widely used in infrared photoelectric detectors and other fields because of their special properties. With the development of larger arrays of mid-infrared focal plane detectors and a growing demand for low-cost InSb infrared detectors, the desired size for the InSb wafers also increases. In this paper, a new structure of graphite rest and high precision low damage single line cutting were combined to develop a 5 inch InSb crystal oriented segmentation. Low damage edge chamfering techniques while optimizing grinding parameters were used to improve the grinding of 5 inch InSb wafers. An optimized mounting process were used to further improve the flatness of polished 5 inch InSb wafers. Furthermore, the pH value and polishing solution ratio were optimized to improve the surface quality of 5 inch InSb wafers. At the same time, the crystal orientation and deviation, polished surface macroscopic quality, geometric parameters, surface roughness and lattice quality of 5 inch InSb wafers were analyzed using an X-ray crystal orientation instrument and atomic force microscope. The test results show that, high quality 5 inch InSb wafers can be created more readily by this newly optimized process, helping to meet the current demand for InSb materials in IR detectors and other fields. [ABSTRACT FROM AUTHOR]

Stripped-back representative VCSEL devices with a simple fabrication process that very closely approaches the performance of standard BCB-planarised devices have been produced. These VCSEL Quick Fabrication (VQF) devices achieve threshold currents only 0.3 mA higher than that of a standard device produced from the same material. The predictability of standard performance from VQF performance is also robustly assessed in terms of temperature effects to account for the observed disparities. These VQF devices are then processed across a 6-inch (152 mm) wafer and the resulting device-level characteristics are mapped. From this, it is apparent that there is an approximately radial decrease in oxide aperture diameter from centre to edge, found to be driven by the strain-induced wafer bow. After corrections, a residual spatial variation across the wafer remains, which, in conjunction with temperature dependent measurements, is shown to be a result of epi-material variation. By observation at 50 °C, that is, at a temperature closely resembling that of intended application, the residual centre-to-edge variation in threshold current density is found to be only 0.2 kA/cm2, compared to 1.3 kA/cm2 when observing the room temperature variation of devices of nominally equivalent active volumes.

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In this study, grape pomace (GP), a by‐product consisting of grape skins and seeds rich in dietary fibres and polyphenols, was used in wafer sheets at different concentrations [5.00 (GP5), 10.0 (GP10), and 15.0 g 100 g−1 (GP15)] for the partial replacement of wheat flour (WF) and improve the functionality of wafer sheets. The GP inclusion at concentrations higher than 5.00 g 100 g−1 significantly affected the texture of sheets as well as the flow behaviour of batters, resulting in softer sheets and more viscous batters (P < 0.05). Moisture contents did not significantly change after GP addition (P > 0.05). After the addition of GP, the L* values decreased and the a* values increased, making the wafers darker (P < 0.05). Moreover, under simulated in vitro digestion conditions, the bioaccessibility of total phenolic compounds in saliva, gastric juice, and intestinal juice was significantly higher than control even at the lowest GP concentration (P < 0.05). Regarding sensory properties, only smoothness and crispness were significantly affected by GP addition, and samples were found to be crisper with higher concentrations of GP. In conclusion, it is possible to partially replace the WF in wafers with GP at a concentration of 5.00 g 100 g−1 to develop a product with higher functionality and nutrient content. [ABSTRACT FROM AUTHOR]

The photovoltaics (PV) industry is booming at an impressive rate. Knowledge of the outdoor performance of different PV technologies under different climatic conditions is becoming increasingly important for all stakeholders. The aim of this research was to perform the outdoor characterization of three PV technologies in a tropical climate and evaluate their performances with the aid of a set of key performance indicators. An innovative energy autonomous outdoor test facility has been used to measure the weather conditions and the IV curves of mono-Si, poly-Si, and Copper Indium Gallium diSelenide (CIGS) PV modules. Each IV curve was sampled within less than a second, for every 10 min, between sunrise and sunset for a whole year, representing a data set of around 28,000 IV curves of 240 points each. The variations of current, voltage, and power were thoroughly studied for changes in temperature and irradiance. This paper reports the variations of temperature coefficients of current, voltage, and power with the intensity of light. While PV module documentation only presents the temperature coefficients of the short circuit current and open circuit voltage at standard test conditions, this paper additionally provides highly valuable information to PV system designers on the variation of these coefficients in the field. The research is also the first to report the variations of the fill factor with temperature and irradiance. In general, the wafer technologies were found to have a better performance than the thin film technology. Moreover, the open-circuit temperature coefficient was found to improve for higher irradiances only for the wafer technologies, while that for the thin-film technology experienced a degradation. The temperature coefficient of current for the mono-Si module was found to be positive at low irradiance levels, but negative at higher irradiance levels. [ABSTRACT FROM AUTHOR]

Stripped-back representative VCSEL devices with a simple fabrication process that very closely approaches the performance of standard BCB-planarised devices have been produced. These VCSEL Quick Fabrication (VQF) devices achieve threshold currents only 0.3 mA higher than that of a standard device produced from the same material. The predictability of standard performance from VQF performance is also robustly assessed in terms of temperature effects to account for the observed disparities. These VQF devices are then processed across a 6-inch (152 mm) wafer and the resulting device-level characteristics are mapped. From this, it is apparent that there is an approximately radial decrease in oxide aperture diameter from centre to edge, found to be driven by the strain-induced wafer bow. After corrections, a residual spatial variation across the wafer remains, which, in conjunction with temperature dependent measurements, is shown to be a result of epi-material variation. By observation at 50 °C, that is, at a temperature closely resembling that of intended application, the residual centre-to-edge variation in threshold current density is found to be only 0.2 kA/cm2, compared to 1.3 kA/cm2 when observing the room temperature variation of devices of nominally equivalent active volumes. [ABSTRACT FROM AUTHOR]

While consumer understanding of and preferences for environmentally friendly packaging options have been well investigated, little is known about the environmentally friendly packaging attributes communicated to consumers by suppliers via packaging cues. We thus propose a literature-based attribute-cue matrix as a tool for analyzing packaging solutions. Using a 2021 snapshot of the wafer market in nine European countries, we demonstrate the tool's utility by analyzing the cues found that signal environmentally friendly packaging attributes. While the literature suggests that environmentally friendly packaging is increasingly used by manufacturers, our analysis of 164 wafer packages shows that communication is very limited except for information related to recyclability and disposal. This is frequently communicated via labels (e.g., recycling codes, Green Dot) and structural cues that implicitly signal reduced material use (e.g., less headspace and few packaging levels). Our attribute–cue matrix enables researchers, companies, and policymakers to analyze and improve packaging solutions across countries and product categories. Our finding that environmentally friendly packaging attributes are not being communicated to consumers underscores a pressing need for better communication strategies. Both direct on-pack and implicit communication should help consumers choose more environmentally friendly packaging. Governments are encouraged to apply our tool to identify communication gaps and adopt labeling regulations where needed. [ABSTRACT FROM AUTHOR]

Since the introduction of adaptive systems for corrective measures, static and dynamic disturbances have been reduced through the manipulation of surface shape in a well-controlled manner. One important application where adaptive systems are highly needed is in the future photo-lithography machines, particularly the wafer table where disturbances affect overlay and focus performance. To reduce overlay and focus errors, a dense array of actuators must be integrated into the wafer table to apply both in- and out-of-plane corrective deformations to the wafer surface. To realize a certain wafer shape, influence functions are linearly superimposed. Accurate models of the influence functions result in an accurate prediction of the final wafer shape. To reduce calibration errors, the influence function of every actuator needs to be determined. Here, we propose a technique to rapidly measure the influence function: the influence function measurement (IFM) technique. Using the actuate-sense property of piezoelectric materials, the influence function is determined by activating one piezo-actuator and measuring the charge induced on the neighboring piezo-actuators. The measured charges are compared to the results of finite element simulations and the absolute difference of 0.3 % is reported for the inter-actuator charge coupling parameters. This clearly indicates the potential of the proposed technique. Note to Practitioners—A critical step during the integrated-circuit lithographic fabrication process is the exposure. A particular practical challenge in this step is to correct for the mismatch between the optical image plane and the wafer surface, caused by wafer deformations. The mismatch negatively impacts the overlay and focus performance. To reduce the mismatch, actuators can be embedded into the wafer table to counteract wafer deformations, where the overall wafer surface shape is a superposition of each actuator’s influence function. As part of the calibration for the embedded actuators, their influence functions are measured and stored. However, errors arise when influence functions are not measured for every actuator. Additionally, for different wafers, the influence functions vary hence the calibration should be done per wafer. This calibration process takes time and should not influence throughput. Our paper presents a viable approach that reduces the calibration time of active wafer tables, which is also relevant for other adaptive systems such as deformable mirrors. Since the technique requires the actuators to be mechanically coupled, it is limited to continuous surfaces. The proposed technique is numerically tested and experimentally verified to demonstrate performance. [ABSTRACT FROM AUTHOR]

To process ingots of FeGa alloy single crystals into wafers, Fe17% Ga alloy crystals were cut using multi-wire sawing or electric discharging and rolling. Further, their properties of magnetization and magnetostriction were analyzed using electron backscatter diffraction (EBSD) and X-ray diffraction (XRD). It was observed that the magnetization and magnetostriction curves changed with increasing rolling reduction. Although magnetization was negligibly affected by deformation, the shape of the magnetostriction curve of the as-grown crystal could be modified by a slight reduction in rolling or a slight plastic deformation. EBSD results show that rolling introduced dislocations to form heterogeneous dislocation cell walls and decreased the surface roughness of the wafers. The pole figures obtained by XRD indicate that the samples were single crystals; however, the crystal orientation was different from the ideal orientation after rolling. Residual stress measurements using the cos ¡ method revealed that compressive and tensile stresses remained in the polycrystalline surface layers of the samples cut by multiwire sawing and electric discharging, respectively. Moreover, the stresses were affected by the tensile strains or magnetic fields when the residual stresses were relatively small in the sample. Although the magnetization and magnetostriction of a single crystal are affected by rolling, they are not significantly reduced by small rolling reductions. [ABSTRACT FROM AUTHOR]

Curcumin is the main active constituent in turmeric, and it is one of the biopolyphenolic compounds. A cumulative body of research supports the use of curcumin in the treatment of wounds, yet poor water solubility and lack of therapeutic dose determination hamper its use for this therapeutic purpose. This work aimed at preparing novel curcumin wafer dressings to provide a favorable environment for wound healing. Hybrid synthetic (PVA, PVP, HPMC, and CMC) and biodegradable (sodium alginate and dextran) polymers were employed to prepare wafer dressings loaded with incremental three doses (2, 10, and 20 mg) of curcumin per a wafer dressing. The solvent casting method was used to prepare the dressings. Dimension, surface pH, mechanical properties, DSC, FTIR, XRD, erosion time, and in vitro release were studied. Skin wound healing assay was studied in Wistar albino rats. Six curcumin-loaded wafers were successfully prepared with good mechanical properties. Curcumin was dispersed in an amorphous/molecular form, as evidenced by thermal (DSC) and spectral (FTIR and XRD) analyses. Prolonged curcumin release (>24 h) was recorded for F6 (10 mg curcumin) and F7 (20 mg curcumin). Wound healing rate constants and time for 50% wound closure (T1/2) were estimated from a semi-log wound diameter versus time curve. A superior healing rate (up to 3-fold faster) was recorded for curcumin-loaded wafer dressings containing 10 mg (F6) with T1/2 of 7 days compared to 20 days for the placebo-treated group. These results warrant using the selected curcumin-loaded wafer dressing for safer and faster wound closure.

This work is devoted to the study of the composition of such a characteristic object for the 17–19 centuries as wafers, which were used to join sheets of paper in documents or to seal letters. Owing to the limited information in the literature and possible degradation processes that may occur with them in this paper, the modern optical techniques were applied to gain information about them. As the object of the investigation the wafers found in the hand-written documents of Academician Friedrich Georg Wilhelm von Struve (Vasily Yakovlevich Struve 1793–1864) were chosen (Fund number 721, the RAS Archive, Saint-Petersburg branch, Struve V.). Besides the common way it was found that a large number of colored wafers were used to join several sheets in one composite elongated document and also to make correction on top of what was written. As the part of a major task aimed at maintaining the fund documents dated 19th century and the stability of the used joining wafers in particular the Raman and UV–Vis absorbance spectroscopies were applied in order to investigate wafers chemical composition. It was found the use of two different types of pigments for orange hues. One of them is cinnabar and another one is made up of red lead and massicot mixture. The Prussian blue was used for wafers with dark blue hue and as a mixture with massicot for green hue. According to UV–Vis absorbance spectroscopy it was found the use of anthraquinone type pigment for the red, rose and purple hues. The presence of the wafers with different base materials were determined by means of the Raman spectroscopy, namely of the vegetable (presumably starch) and protein (presumably gelatin) origin. The obtained results were compared with the data available in the previous researches, including the recipes given in the publications of the 19th century. [ABSTRACT FROM AUTHOR]

Wafer-scale single-crystal graphene with strong antioxidation is fundamentally important for their applications in electronics and optoelectronics. Although significant progress has been achieved in the chemical vapor deposition (CVD) growth of graphene, the production of wafer-scale graphene with high crystalline and excellent oxidation resistance still remains a challenge. Here, we report the epitaxial growth of 6-inch single-crystal graphene on twinned Pt (111) films with in-plane rotation of 60°(T-Pt) by ambient-pressure CVD. Our results show that the CVD-grown graphene on T-Pt exhibits fast growth rate and ultrahigh stability under the high-temperature air condition (>500 °C). The density functional theory (DFT) calculations reveal that the twinned Pt(111) surface does not change the preferential orientation of graphene nucleation, leading to highly aligned graphene domains on the T-Pt substrate. Moreover, the edge growth of graphene cannot be limited by the Pt twin boundaries (TBs), which is responsible for the fast growth of graphene single crystals. This work provides a reliable route to produce wafer-size single-crystal graphene monolayers with excellent oxidation resistance and clarifies the oriented growth mechanism of graphene domains on twinned Pt substrate. Here, we report an oriented multi-nuclei growth strategy toward 6-inch single-crystal graphene on twinned Pt (111) films with in-plane rotation of 60° (T-Pt) by ambient-pressure chemical vapor deposition. The graphene on Pt grows fast and has better oxidation resistance than graphene on Cu substrate. The density functional theory (DFT) calculations reveal that Pt-twinned structure does not change the preferential orientation of graphene nuclei, resulting in highly oriented graphene domains on the T-Pt substrate. This work provides a reliable approach to produce wafer-size single-crystal graphene monolayers with excellent oxidation resistance and clarifies the oriented growth mechanism of graphene domains on T-Pt substrate. [Display omitted] [ABSTRACT FROM AUTHOR]

A novel ice particle-fixed abrasive tool (IPFAT) was designed and manufactured in this paper. The uniformity of abrasives distribution in the IPFAT was tested. Using three kinds of IPFAT, which contains α-Al2O3 particles whose mean particle sizes are 5 μm, 1.289 μm, and 0.328 μm respectively; single crystal germanium wafers were lapped and then polished. The results show that the distribution of abrasives in the IPFAT is uniform and the IPFAT has the ability of self-sharpening. With the increased lap and polishing time, the surface roughness of the single crystal germanium wafers decreases linearly and the materials remove rate (MRR) basically remains invariable. After polishing with a 0.328 μm α-Al2O3 IPFAT, the surface roughness of the single crystal germanium wafer is 85 nm within 500 μm × 500 μm and the surface is even without obvious undulation. [ABSTRACT FROM AUTHOR]

Self-assembled layers of aminosilane have been used to bind nanoparticle catalysts for electroless deposition on silicon wafers. However, the influence of accessible amino groups on aminosilane on the adhesion of nickel-phosphorus (Ni-P) deposits has not yet been determined. In this study, we deposited (3-aminopropyl)trimethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, and 3-(trimethoxysilylpropyl)diethylenetriamine as coupling layers between Ni-P films and silicon substrates. We explored the influence of different aminosilanes on the distribution of the catalysts and the adherence of electroless Ni-P films. The surface morphology, composition, and hardness of Ni-P films formed on the different aminosilanes were thoroughly examined. The results indicate that 3-(trimethoxysilylpropyl) diethylenetriamine can bind to the largest number of nanoparticles, but the lack of anchoring sites and catalyst aggregation accounted for the poor adhesion of the Ni-P film deposited on it. [ABSTRACT FROM AUTHOR]