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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]

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]

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.

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.

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]

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.

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]

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]

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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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]

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.

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]

The increasing demand for single-crystal wafers combined with the increase in diameter of semiconductor wafers has warranted further improvements in thickness variation and material removal rate during lapping to ensure price competitiveness of wafers; consequently, the lapping process has gained the attention of researchers. However, there is insufficient research on the effect of platen grooves on the lapping process. In this study, the parameters to describe grooves were defined in order to understand their influence on the lapping process, and a material removal model was suggested based on indentation theory and subsequently experimentally validated. The results indicate that changes in groove density affect the lubrication condition at the contact interface as well as the probability of abrasive participation by varying the oil film thickness. When fabricating the groove for a lapping platen, a groove density at the critical groove density (CGD) or higher should be selected. The higher the groove density, the easier it is to avoid the CGD, and the higher is the material removal rate. The results of this study will enable engineers to design lapping platen grooves that are suitable for the production of modern semiconductor wafers. [ABSTRACT FROM AUTHOR]

Magnetorheological finishing, considered as a promising polishing technique that can finish a nano-level smooth surface and free of surface or subsurface damage, has been widely utilized in ultra-smooth polishing of hard-to-machine materials. However, there are still several practical weaknesses in magnetorheological finishing (MRF) applied for wafer surface polishing. In this study, a new method using MRF effect was proposed for wafer polishing. Concretely, porous foam was used as a storage carrier of MR slurry, and thus, MR slurry can be bounded in porous foam in the finishing process (cluster MR-porous foam polishing, CMRPP). In this paper, an experimental rig was constructed to achieve CMRPP mechanism, the processing principle and material removal process in CMRPP were analyzed, and CMRPP experiments were conducted to investigate the effects of porous foam on surface polishing. The results indicate the following: (1) The polishing forces in CMRPP were increased compared to that of a cluster MR polishing without porous foam (CMRP), and CMRPP can get a greater shear force than of CMRP at a same normal force; (2) CMRPP can well hinder the solid-liquid separation and sustain the stability of the slurry performance; (3) CMRPP achieved a higher volumetric removal rate than that of CMRP and improving of material removal efficiency; (4) CMRPP can effectively achieve a nano-level smooth surface compared to that of CMRP. [ABSTRACT FROM AUTHOR]

Diamond (111) plane is superior in impurity doping and quantum spin control to (100) plane, however, there are many technical issues in mass production of the substrate, such as a smaller seed substrate size, low removal rate of polishing, and low growth rate. In this study, a large (111) single crystal diamond substrate of 7 mm × 6 mm was fabricated by growing and processing bulk (100) CVD single crystal. Furthermore, using this as a seed substrate, a (111) self-standing plate was fabricated using the lift-off method. The FWHM of the X-ray rocking curve was 46 arcsec and that of the Raman peak was 2 cm−1. This method can be applied to fabrication of any high index plane such as (113) and can be utilized to fabrication of substrate for electronic and quantum devices, device processing to fabricate vertical structure. [Display omitted] • (111) single crystal diamond (SCD) substrate was formed by processing (100) bulk SCD. • A 7 mm × 6 mm, one of the largest (111) homoepitaxial SCD substrates was obtained. • (111) self-standing cloned SCD plate was fabricated using lift-off method. • This fabrication process can be applied to form a high index plane such as (113). • This method is useful for fabrication of SCD electronic and quantum devices. [ABSTRACT FROM AUTHOR]

A material removal rate (MRR) model as a function of abrasive weight concentration has been proposed by extending a material removal model developed earlier [1-2]. With an increase of the weight concentration of abrasives/MRR, three regions of material removal exist: first, a chemically dominant and rapid increasing region, whose range is determined by the generation/passivation rate and hardness of the surface passivation layer, second, a mechanically dominant linear region, where the material removal is proportional to the weight concentration, and third, a mechanical dominant saturation region, where the material removal saturates because the total contact area is fully occupied by the abrasives. The passive layer of the wafer surface is proposed to be a bi-layer structure. In the first part of this paper, a detailed model is proposed to explain that the transition from the first to the second region is due to a transition from a wafer surface covered with a single soft material to a surface covered with both soft and hard materials. The chemicals contribute to the material removal through the generation rate of the upper softer layer of the passive films. The slope of the linear region is a function of abrasive size distribution, and the saturation removal rate is a function of abrasive size distribution and wafer-pad contact area. These are supported by experimental results to be discussed in the second part of this paper [39]. The model can help to clarify the roles of chemicals, wafer-pad contact area and abrasive size distribution in chemical mechanical polishing.

The increasing demand for single-crystal wafers combined with the increase in diameter of semiconductor wafers has warranted further improvements in thickness variation and material removal rate during lapping to ensure price competitiveness of wafers; consequently, the lapping process has gained the attention of researchers. However, there is insufficient research on the effect of platen grooves on the lapping process. In this study, the parameters to describe grooves were defined in order to understand their influence on the lapping process, and a material removal model was suggested based on indentation theory and subsequently experimentally validated. The results indicate that changes in groove density affect the lubrication condition at the contact interface as well as the probability of abrasive participation by varying the oil film thickness. When fabricating the groove for a lapping platen, a groove density at the critical groove density (CGD) or higher should be selected. The higher the groove density, the easier it is to avoid the CGD, and the higher is the material removal rate. The results of this study will enable engineers to design lapping platen grooves that are suitable for the production of modern semiconductor wafers.

• This mini-review provides a thorough overview of current buccal/oral lyophilizates. • The mini-review discusses material and process parameters using the quality by design (QbD) approach. • This study covers trends in experimental buccal/oral formulations. • It relates drug and dosage form limitations to aid future developments. • It shows buccal/oral lyophilizates as safe and effective prominent drug delivery systems. A great number of patients have difficulty swallowing or needle fear. Therefore, buccal and orodispersible dosage forms (ODFs) represent an important strategy to enhance patient compliance. Besides not requiring water intake, swallowing or needles, these dosage forms allow drug release modulation. ODFs include oral lyophilizates or wafers, which present even faster disintegration than its compressed counterparts. Lyophilization can also produce buccal wafers that adhere to mucosa for sustained drug release. Due to the subject relevance and recent research growth, this review focused on oral lyophilizate production technology, formulation features, and therapy gains. It includes Critical Quality Attributes (CQA) and Critical Process Parameters (CPP) and discusses commercial and experimental examples. In sum, the available commercial products promote immediate drug release mainly based on biopolymeric matrixes and two production technologies. Therapy gains include substitution of traditional treatments depending on parenteral administration and patient preference over classical therapies. Experimental wafers show promising advantages as controlled release and drug enhanced stability. All compiled findings encourage the development of new wafers for several diseases and drug molecules. [ABSTRACT FROM AUTHOR]

Freeze-dried elderberry and chokeberry were proposed as natural colorants for gluten-free wafers. In addition to colour, other physical and sensorial properties of wafer sheets were also evaluated. The elderberry powder was significantly darker (L* equal 37.61) than the chokeberry powder (L* equal 41.01), and it was characterized by a considerably lower a* value (4.21 in comparison with 12.32). These powdered fruits were added in the range from 0 to 5%. A new indicator of wafer batter delamination was developed, which can also be proposed for other liquids. Significant and favourable changes were noted in the colour of both batter and wafers, with an increased content of fruits from 1 to 5%. Gluten-free wafers with a 5% addition of fruits were characterized by L*, a*, b* values, respectively, equalling 35.73, 6.05 and 3.24 for elderberry, and 39.74, 7.15 and 5.05 for chokeberry. Wafers with a 5% addition of chokeberry and elderberry, in comparison to control wafers, had significantly higher contents of minerals, including iron, potassium, calcium, magnesium and sodium. The freeze-dried elderberry powder, as compared to the chokeberry powder, was found to significantly increase the content of these minerals. In addition, the total flavonoids content was higher in the wafers containing elderberry. Freeze-dried chokeberry and elderberry can be proposed as natural colorants and valuable functional components for wafers. [ABSTRACT FROM AUTHOR]

Lawrence Kleinberg Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University, Baltimore, MD, USA Abstract: Polifeprosan 20 with carmustine (GLIADEL®) polymer implant wafer is a biodegradable compound containing 3.85% carmustine (BCNU, bischloroethylnitrosourea) implanted in the brain at the time of planned tumor surgery, which then slowly degrades to release the BCNU chemotherapy directly into the brain thereby bypassing the blood–brain barrier. Carmustine implant wafers were demonstrated to improve survival in randomized placebo-controlled trials in patients undergoing a near total resection of newly diagnosed or recurrent malignant glioma. Based on these trials and other supporting data, carmustine wafer therapy was approved for use for newly diagnosed and recurrent malignant glioma in the United States and the European Union. Adverse events are uncommon, and as this therapy is placed at the time of surgery, it does not add to patient treatment burden. Nevertheless, this therapy appears to be underutilized. This article reviews the evidence for a favorable therapeutic ratio for the patient and the potential barriers. Consideration of these issues is important for optimal use of this therapeutic approach and may be important as this technology and other local therapies are further developed in the future. Keywords: carmustine, wafer, gliadel, glioblastoma