Vertical Holes Research Articles

Ultralow-Power Programmable 3D Vertical Phase-Change Memory with Heater-All-Around Configuration.

Recent advancements in phase-change memory (PCM) technology have predominantly stemmed from material-level designs, which have led to fast and durable device performances. However, there remains a pressing need to address the enormous energy consumption through device-level electrothermal solutions. Thus, the concept of a 3D heater-all-around (HAA) PCM fabricated along the vertical nanoscale hole of dielectric/metal/dielectric stacks is proposed. The embedded thin metallic heater completely encircles the phase-change material, so it promotes highly localized Joule heating with minimal loss. Hence, a low RESET current density of 6-8 MAcm-2 and operation energy of 150-200 pJ are achieved even for a sizable hole diameter of 300nm. Beyond the conventional 2D scaling of the bottom electrode contact, it accordingly enhances ≈80% of operational energy efficiency compared to planar PCM with an identical contact area. In addition, reliable memory operations of ≈105 cycles and the 3-bits-per-cell multilevel storage despite ultrathin (<10nm) sidewall deposition of Ge2Sb2Te5 are optimized. The proposed 3D-scaled HAA-PCM architecture holds promise as a universally applicable backbone for emerging phase-change chalcogenides toward high-density, ultralow-power computing units.

Simulation of light environments inside lunar holes and their associated subsurface caverns

Vertical holes of several tens of meters in diameter and depth have been discovered on the Moon, potentially serving as skylights into subsurface volcanic caverns resembling lava tubes. Because of their scientific importance and potential for use as future lunar bases, these lunar holes and caverns are expected to be targets of intensive exploration in the near future. Using numerical simulations, this study investigates the light environment within a directly and/or indirectly sunlit subsurface cavern accessed through a skylight hole. We specifically analyze the Mare Tranquillitatis Hole (MTH), one of the largest lunar vertical holes, situated near the Moon's nearside meridian. The floor and walls of the hole, and the walls and ceiling of its associated subsurface cavern are lit by reflected sunlight from other parts of the hole and cavern, such as the floors, depending on the solar elevation angle. Furthermore, this paper presents estimation results for camera imaging for a case in which solar elevation angle is 45° in the morning, which is appropriate timing for exploration. Assuming reflectance of 0.1 for the lunar hole and cavern surfaces, we estimate the incident energy onto each pixel of a camera as it descends to the hole's floor. We specifically simulate conditions for a camera with a 12-bit dynamic range, similar to the wide-angle optical navigation camera (ONC-W) onboard the Hayabusa 2 spacecraft. The results suggest that a camera with a fixed gain would struggle to capture both directly and indirectly sunlit areas simultaneously, without saturating bright areas and ensuring minimum incident energy resolution (say, a 10 digital number) for darker areas. To overcome this challenge, adjusting the camera gain based on the hole's and cavern's illumination conditions is necessary.Graphical abstract

The impact of pulsed Nd:YAG laser on the surface of n-Si and photo-electrical performance of silicon solar cells

Texturizing the surface of a silicon solar cell enhances performance by reducing reflection losses. Pyramidal texturization via wet chemical etching is standard in manufacturing, while plasma etching is often used for vertical hole texturization. Laser texturization offers a chemical-free, user-friendly alternative to plasma etching. Infrared (IR) transmission studies indicate that laser-textured samples transmit more IR light through n-Si than normally textured samples, suggesting that vertical grooves from laser texturization allow deeper light penetration. Analyses using cross-sectional Field Emission Scanning Electron Microscopy (FESEM), Energy Dispersion x-ray (EDX), and Energy Dispersive Spectroscopy (EDS) demonstrate the effects of laser texturization on the front surface of textured n-Si wafers. However, silicon solar cells with laser-textured surfaces demonstrated lower conversion efficiencies (1.20% to 4.30%) compared to conventionally textured cells (14.30%). The short-circuit current density (JSC) was also lower in laser-textured cells, below 17 mA cm−2, compared to 34.44 mA cm−2 in normally textured cells. At the same time, higher laser power (114 W) during texturization also led to the lowest JSC and open-circuit voltage (VOC), indicating that laser texturization may introduce defects and dislocations that degrade Si properties.

Validation of McCARD Monte Carlo Calculation Code Against NAA Experiments Using Rare Earth Element Certified Reference Material Activated at JRTR

Rare earth elements (REEs) are widely used in several high-tech modern industries. Quantification of REEs demonstrates a technical challenge that requires the use of special scientific techniques. These techniques commonly introduce uncertainties that may propagate not only during the sample preparation phase but also in subsequent measurement and analysis phases. The Jordan Atomic Energy Commission is starting up a REE investigation program utilizing many of its available physical and chemical analytical capabilities, one of which is the Neutron Activation Analysis Facility (NAAF) at the Jordan Research and Training Reactor (JRTR). The NAAF provides accurate and relatively quick analytical services for better estimations of REEs in the unknown samples of interest without the need for any chemical processing prior to or after sample activation. In this paper, we present analytical results of routinely conducted instrumental neutron activation analysis (NAA) experiments using REE certified samples. To optimize future NAA investigations, first, a time-dependent Monte Carlo code at the JRTR, named Monte Carlo Code for Advanced Reactor Design and Analysis (McCARD), is herein validated via comparing its calculation results of the activation process against the presented results of the NAA experiments. The certified REE samples were activated in a well-thermalized NAA vertical activation hole within the reactor reflector region. Detailed neutronics and burnup calculations as well as transmutations were performed using McCARD. Ultimately, this study aims to assess the accuracy and reliability of the McCARD calculation models as a part of the effort of setting up a dedicated REE analysis laboratory at the JRTR. This study shows very good agreement between both obtained results—NAA experiment and McCARD calculations—with confidence levels noted to be more than 90% for almost all REE elements.

Study on the Natural Smoke Exhaust Performance of Board-Coupled Vertical Shaft in High-Altitude Tunnel Fires

Vertical shaft natural ventilation is a common smoke exhaust method in highway tunnel fires. This study investigated the vertical shaft natural smoke exhaust work in highway tunnel fires with the effect of multiple factors through numerical simulation. Using the analysis of the flow field of smoke in nearby areas of the vertical shaft and the quantitative calculation of the gas exhausted through the vertical shaft, considering the impact of shaft division and board height, an optimal vertical shaft arrangement was proposed, and the working conditions of this arrangement in low-pressure environments were discussed. The results show that dividing a single large vertical shaft into multiple small vertical shafts and appropriately adjusting the board height can reduce the incidence of vertical shaft plug holes and significantly enhance the vertical shaft smoke exhaust performance. Meanwhile, the board-coupled shaft (BCS) has excellent working ability in low-pressure environments, and when pressure drops, smoke exhaust efficiency will improve. This research offers a foundation and reference value for improving the vertical shaft smoke exhaust system in highway tunnels.

Retrofitting intact and heat-damaged shear-deficient concrete beams using CFRP ropes and dowels

The potential for recovering the shear capacity of heat-damaged beams using carbon-fibre-reinforced polymer (CFRP) ropes was investigated using 12 concrete beams (150 × 250 × 1450 mm3) with shear reinforcement deficiency. Six beams were heated for 2 h at a temperature of 400°C; the others were not heated. All the beams were retrofitted with near-surface mounted CFRP ropes as external U-shaped stirrups, inserted in vertical holes (embedded through reinforcement) or implemented as a hybrid system of both. Lateral dowels were implanted in concrete along with schemes involving U-shaped stirrups to improve resistance against cover separation and shear failure, respectively. The mechanical behaviour of the beams was evaluated under three-point loading, with data collected and analysed to characterise the load–deflection relationships. Cracking and failure modes were analysed. For the heat-damaged beams, the adopted schemes restored load capacity and improved toughness and ductility, but not flexural stiffness. Moreover, implementing ropes as U-shaped external stirrups, terminating 20 mm below the top surface of the beams, helped avert side-cover separation, yet resulted in horizontal shear failure at the level of the upper concrete cover of the damaged beams. The residual strain induced in the U-shaped external stirrups was 14–40%, which is compatible with those reported in other works adopting similar repair methodologies.

Investigation of the radiated emission of honeycomb structured aluminum foam/cellular heatsinks at 1–10 GHz

Metal foams or cellular structures like honeycombs, can also be evaluated according to mechanical, acoustic, thermal, and chemical resistance parameters in terms of functionality. However, it is vital to investigate the performance of these cellular structures' radiated emission (RE), which can be used as PCB heatsinks. In this study, the radiated emission (RE) performance of honeycomb-structured aluminum foam (or cellular) heatsinks (AFH), which can be considered as unidirectional regular foam, is examined in the frequency range of 1–10 GHz as a novelty. Also, the effect of four primary variables (the geometry of AFH, honeycomb hole direction, honeycomb cell size, and honeycomb cell wall thickness) on the RE performance of AFH is investigated. Unlike classical honeycomb production methods, the investment flask mold casting (loss wax) method is preferred due to the complex offset strip geometry of designed honeycombs. The original design offset hexagonal honeycomb structures were successfully produced using this investment casting method with additive manufacturing technologies from molten metal. While all simulations are carried out using CST Studio Suite, the RE performance of the proposed AFHs is measured in a standard 3 m fully anechoic chamber using a reference horn antenna and vector network analyzer (VNA). When the results are examined, the measured and simulated results agree with each other quietly. Regarding RE, structures with a CPI value of 14 are better at low frequencies, while structures with a CPI value of 3.5 are better at high frequencies. Secondly, the honeycomb cell thickness value does not significantly affect EMI performance. Lastly, although there is no significant difference in EMI in the low-frequency region, it is better to use a directional structure with vertical holes in the high-frequency region. As a result, in the design of AFH, the RE performances of the heatsinks and their thermal performance should be considered.

Hole Generation in Polarization‐Doped AlxGa1–xN (x = 0.9–0.35)‐Graded Layer with Heavily Mg‐Doped Al0.35Ga0.65N Contact Layer for 275 nm Deep‐Ultraviolet Light‐Emitting Diode

Herein, hole generation in a 60 nm thick polarization‐doped AlxGa1–xN (x = 0.9–0.35)‐graded layer with some Mg doping (5 × 1018 cm−3) is demonstrated by using a 10 nm thick heavily (1 × 1020 cm−3) Mg‐doped Al0.35Ga0.65N contact layer. First, light emission from a deep‐ultraviolet light‐emitting diode is observed with the AlxGa1–xN (x = 0.9–0.35)‐graded layer and the Al0.35Ga0.65N contact layer, indicating a vertical hole transport from the Al0.35Ga0.65N contact layer to the active region through the polarization‐doped AlGaN‐graded layer. Second, hole concentration, mobility, and resistivity values of the AlxGa1–xN (x = 0.9–0.35)‐graded layer and the Al0.35Ga0.65N contact layer are evaluated by Hall effect measurement. A hole concentration of 1.8 × 1018 cm−3 is clearly observed by removing the AlGaN contact layer (not underneath of electrodes) to minimize a parallel conduction. The hole concentration shows a very weak temperature dependence from room temperature down to 150 K, suggesting that the holes are generated by polarization doping. Hole generation in the fully strained AlxGa1–xN (x = 0.9–0.35)‐graded layer is directly evaluated by Hall effect measurement with the AlGaN contact layer just underneath the electrodes.

High Vertical Hole Mobility through Minimization of Water-Induced Traps by F4TCNQ Doping in Conjugated Amphiphilic Diblock Copolymers

High Vertical Hole Mobility through Minimization of Water-Induced Traps by F4TCNQ Doping in Conjugated Amphiphilic Diblock Copolymers

Plasma-based etching approach for GEM detector microfabrication at FBK for X-ray polarimetry in space

Gas Electron Multiplier (GEM) detectors are crucial for enabling high-resolution X-ray polarization of astrophysical sources when coupled to custom pixel readout ASIC in Gas Pixel Detectors (GPD), as in the Imaging X-ray Polarimetry Explorer (IXPE), the Polarlight cubesat pathfinder and the PFA telescope onboard the future large enhanced X-ray Timing and Polarimetry (eXTP) Chinese mission. The R&D efforts of the IXPE collaboration have resulted in mature GPD technology. However, limitations in the classical wet-etch or laser-drilled fabrication process of GEMs motivated our exploration of alternative methods. This work focuses on investigating a plasma-based etching approach for fabricating GEM patterns at Fondazione Bruno Kessler (FBK). The objective is to improve the aspect ratio of the GEM holes, to mitigate the charging of the GEM dielectric which generates rate-dependent gain changes. Unlike the traditional wet-etch process, Reactive Ion Etching (RIE) enables more vertical etching profiles and thus better aspect ratios. Moreover, the RIE process promises to overcome non-uniformities in the GEM hole patterns which are believed to cause systemic effects in the azimuthal response of GPDs equipped with either laser-drilled or wet-etch GEMs. We present a GEM geometry with 20 μm in diameter and 50 μm pitch, accompanied by extensive characterization (SEM and PFIB) of the structural features and aspect ratios. The collaboration with INFN Pisa and Turin enabled us to compare the electrical properties of these detectors and test their performance in their use as electron multipliers in GPDs. Although this R&D work is in its initial stages, it holds promise for enhancing the sensitivity of the IXPE mission in X-ray polarimetry measurements through GEM pattern with more vertical hole profiles. The outcomes of this study have the potential to advance the current technological platforms and improve the capabilities of future space-based X-ray polarimetry missions.

Enhanced hole transport of nonpolar InGaN-based light-emitting diodes with lateral p-type superlattice doping structure

In this work, we propose a novel structure for nonpolar (10–10)-plane InGaN-based light-emitting diode (LED) using a lateral p-type Al0.2Ga0.8N/GaN superlattice structure as the hole injection layer. The main objective is to increase the hole concentration and facilitate vertical hole injection. The nonpolar InGaN-based LED lacks polarization along the growth plane (10–10), but the lateral direction along [0001] exhibits strong polarization. Therefore, the Al0.2Ga0.8N/GaN superlattice structure, which is periodic along the [0001] direction, induces net polarization charges at the GaN/Al0.2Ga0.8N interface, resulting in increased ionization rates of the acceptors. Additionally, the high-density two-dimensional hole gases formed at the Al0.2Ga0.8N/GaN interfaces along the [0001] direction can efficiently inject vertically into the quantum wells. Based on the numerical simulation results, the proposed LED structure offers improved electrical characteristics, effective hole injection, and enhanced optical performance compared to the nonpolar LED with conventional p-type doping structure.

Two-dimensional (2D) axis-pin force sensor and its characterization on the shear force direction

The characterization of the shear force direction is an imperative technical problem to be solved for the axis-pin force sensor. In the present work, a two-dimensional axis-pin force sensor has been designed. The layout of the sensor is to open horizontal blind holes and vertical blind holes at intervals of 90 degrees along the circular direction on the surface of the axis-pin. Then the variation law of the circumferential strain of blind holes along with the shear force direction is first studied through the FEA simulation. It is found that the sum of the circumferential strains of two horizontal blind holes or vertical blind holes varies in sine and cosine pattern with the shear force direction. On this basis, the mathematical model of shear force direction characterized by circumferential strains of blind holes is derived. Eventually, the prototype of the axis-pin force sensor was made to verify this law. The experimental results showed that the accuracy of the shear force and direction measured by the sensor can reach ± 8% and ± 5% respectively, which meet the requirements of the practical application. This method eliminates the theoretical error caused by the use of correction coefficients and nonlinear model approximation, which provides a theoretical basis for the development of two-dimensional axis-pin force sensors.

Improvement Plan Using Fatigue Analysis Minimizes Jar Twistoff

_ This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 210723, “Service Quality Improvement Plan Using FEA Fatigue Analysis Minimizes Jar Twistoff in Challenging Applications,” by Chaouki Boufama, SPE, Baozhong Yang, and Sultan Alfaraedhi, Schlumberger, et al. The paper has not been peer reviewed. _ Jar twistoff is a well-known service quality issue for some applications, especially in relatively large borehole sizes such as 22 and 16 in. The jar is one of the weakest points in the drillstring because of moving parts, which include complex shapes, resulting in stress concentration. The complete paper presents results of a study focusing on placing the jar in the bottomhole assembly (BHA) to reduce bending moments and bending stresses on the jar connections. As a result, the risk of twistoffs during drilling is minimized, while the effectiveness of the jar is maintained if a stuck event occurs. Introduction Jars traditionally are placed between drill collars in the applications described in this study. These applications include 22- and 16-in. vertical holes with simple BHA designs, either rotary or with positive displacement motors. In cases of lateral vibration that creates high bending stress, this design is likely to cause the jar to experience extreme stress levels. The design concept of placing the jar between other components with lower weight and stiffness appears to be the most logical approach. This design would have to be validated with finite element analysis (FEA) dynamic modeling simulations to confirm lower stress at the jar and that a new weak point has not been introduced in the string. Impact and impulse also must be evaluated to confirm the effectiveness of the jar in the case of a stuck-pipe condition. The study is based on the work flow shown in Fig. 1 of the complete paper. Statement of Theory and Definitions A more in-depth analysis was performed on a 22-in. vertical drilling application with nonhomogeneous formations. A downhole real-time recording tool was added to the drillstring above the BHA to evaluate and verify the magnitude of vibration and bending moments acting on the BHA during drilling operations. The 22-in. vertical section was selected because it was determined to be the most challenging section. The following key observations were made during the drilling run when the circulation was lost to the formation: - Significant lateral vibration levels - Chaotic whirling motions - High bending moment Mechanical specific energy (MSE) and drilling parameters were controlled during the run to alleviate vibration. Vibration severity could have been influenced by the absence of the mud column as well as the borehole quality because of formation washout and an oversized hole. However, this was never verified using a caliper log. The string entered a state of chaotic whirl as the loss of circulation fluid began. The parameters, and thus the MSE, were reduced, but the severe vibrations persisted. Even though the run did not cause any jar-component failure or crack, multiple previous incidents showed similar failure modes in the same downhole conditions. These failures, which included the fractured face of each of the parted components, were analyzed and evaluated (Fig. 1). The slanted fracture indicated a high combined stress-related fracture. In addition, beach marks present near the fracture area also indicated fatigue-induced damage.

Development of a novel cartridge for expansive cement application to hard rock breakage

ABSTRACT Expansive cement (EC) is generally a slurry that it is poured into vertical holes for surface rock breakage applications. This paper describes the development of a novel cartridge for extending EC applications from gravity-filled vertical holes to horizontal, uptilted, and wet boreholes. Four cartridge prototypes were made from low-cost and readily available plastics using three-dimensional printers. The performance of each cartridge was investigated in unconfined rock slab tests. The polylactic acid (PLA) cartridge was found to be superior to the thermoplastic polyurethane, polyethylene terephthalate glycol, and acrylonitrile butadiene styrene cartridges. Through partial heat containment, the PLA cartridge accelerated the EC hydraulic reaction and shortened the onset of rock destruction by 30% relative to vertical, gravity-filled EC. Finally, rock breakage with EC was demonstrated in an underground mine using PLA cartridges. This novel type of cartridge could not only suit various applications beyond the scope of the current EC surface applications but also significantly improve the rock fracturing efficiency of EC.

Novel SOFC Repeating Unit Design for the Uniform Distribution of Temperature and Thermo-Electrochemical Reaction Zone in a Commercial Scale Stack

Despite the substantial benefits provided by solid oxide fuel cell (SOFC), its low durability at high-temperature hydrocarbon-fueled operations has inhibited widespread market deployment. Thanks to the tremendous efforts of researchers, SOFC has exhibited sufficient performance to compete with other power generation technologies in the market. However, the lifespan problem due to long-term degradation remains the final obstacle for large-scale deployment. Especially when the hydrocarbon is used as fuel to take an advantage of fuel flexibility, carbon deposition can worsen the problem.A conventional crossflow type stack has the advantage of small volume, which can increase the power and energy density, but suffereing from large nonuniformities of temperature and thermo-electrochemical reactions. However, it has nonuniform temperature and species distribution, where thermo-electrochemical reactions are concentrated at the fuel inlet region. These imbalanced distributions of temperature and species are the major limitation of conventional design since certain regions of the stack are inevitably exposed to a much harsher environment than the remaining regions. For example, nickel reoxidation may occur where fuel is depleted, interfacial separation due to high polarization may appear where electrochemical reactions are concentrated, and carbon deposition may be developed where thermochemical reactions extremely occur. These specific regions might be degraded much faster than the remaining, which can threaten the entire stability of the stack.In this study, we present the novel SOFC stack design that can solve the instability problem of the conventional crossflow type design. First, the vertical gas manifold holes are rearranged to be placed in all perimeters, symmetrical in both diagonals [1]. Since this arrangement makes the stack consist of four symmetric parts, all thermodynamic variables and chemical reactions are distributed symmetrically, and the temperature gradient in the planar direction can be reduced. Second, the guide rib pattern and flow resistance field in the interconnect are optimized to have uniform gas distribution [2]. Finally, a new component, called a ‘cover’, is added in between the interconnect and cell to control the mass transport in a vertical direction [3]. Through the control of mass transport in the vertical direction, chemical reactions can occur in much larger regions rather than concentrated in the fuel inlet regions. To verify the advantages of the novel design, we compare it with the conventional design through the three-dimensional numerical model [4]. As shown in Figure 1, the nonuniformities of temperature, fuel concentration, and chemical reaction are improved through the design modification. Compared to the conventional design, the standard deviations of each variable in the novel design are decreased by 65.07%, 25.14%, and 20.28%, respectively. Entire design processes, various simulation results, and detailed analysis will be provided.

Mechanical influence of tissue scaffolding design with different geometries using finite element study.

The mechanical properties of tissue scaffolds are essential in providing stability for tissue repair and growth. Thus, the ability of scaffolds to withstand specific loads is crucial for scaffold design. Most research on scaffold pores focuses on grids with pore size and gradient structure, and many research models are based on scaffolding with vertically arranged holes. However, little attention is paid to the influence of the distribution of holes on the mechanical properties of the scaffold. To address this gap, this research investigates the effect of pore distribution on the mechanical properties of tissue scaffolds. The study involves four types of scaffold designs with regular and staggered pore arrangements and porosity ranging from 30% to 80%. Finite element analysis (FEA) was used to compare the mechanical properties of different scaffold designs, with von-Mises stress distribution maps generated for each scaffold. The results show that scaffolds with regular vertical holes exhibit a more uniform stress distribution and better mechanical performance than those with irregular holes. In contrast, the scaffold with a staggered arrangement of holes had a higher probability of stress concentration. The study emphasized the importance of balancing porosity and strength in scaffold design.

APLIKASI LUBANG RESAPAN BIOPORI BERKOMPOS DI KEBUN KOPI MENINGKATKAN JUMLAH SPORA MIKORIZA ARBUSKULA DAN KOLONI AKAR

Mycorrhizae is a mutualistic symbiotic relationship between fungi and plant roots, and soil characteristics influence the performance of this symbiosis. Biopore Infiltration Hole is a vertical hole into the soil with a diameter of about 10cm and at a depth of ±100 cm in the soil for air infiltration, which is helpful in reducing the occurrence of excessive air puddles. This research was conducted to determine the effect of soil properties such as pH, total N, available P, CEC and texture on the number of spores and root colonies by arbuscular mycorrhizae on the effect of biopore infiltration holes with the addition of organic matter. The results showed that the highest number of arbuscular mycorrhizae spores and root colonies was in the biopore infiltration holes with goat manure, namely 16.3 spores 100 g-1 soil and 66.22% root colonization. The arbuscular mycorrhizal genera found included Glomus, Acaulospora, Scutellospora, and Gigaspora. The number of spores and soil properties that were positively correlated were pH (r=0.45), organic C (r=0.945**), total N (r=0.716**), available P (r=0.922**), dan CEC (r=0.894**).

Application of electrical resistivity tomography (ERT) for vertical high-density polyethylene (HDPE) membrane detection

At landfill sites, uncontrolled leachate is a serious cause of groundwater and soil contamination at landfills and can occur extensively when there are looploopholesin the vertical HDPE (High-density polyethylene) membrane. For this reason, detecting HDPE membranes is necessary. The conventional electrode running poles approach is limited, it reflects the distribution of resistivity in 2D subsurface profiles, which is difficult to deploy electrodes above vertical HDPE membrane. According to the structural characteristics and field conditions of vertical HDPE membranes, the two-row current and potential (CP) electrode array is proposed to be applied to the testing of vertical HDPE membranes. The forward geoelectric model of the vulnerability was built using pyGimli, and data on 1519 apparent resistivity were acquired. The previous knowledge without the vulnerability was taken into consideration as the constraint condition, and the regional control was added to conduct the inversion, all using the least square approach. The model was used to analyze data on the detection of vertical HDPE membranes in a landfill In Yancheng, and potential flaws were discovered. Results show that the CP electrical measuring device can be efficient, quick, and accurate in the positioning of vertical HDPE membrane hole detection, and it is a cost-effective method. To verify the results, in the vertical HDPE membrane, through the Wenner device, the inversion of the 2D profile, and low resistivity anomalies are detected. This is thought to be through the leachate of leakage of HDPE membrane resistance rate is about 1.8 ohm. The findings demonstrate that the vertical HDPE membrane susceptibility may be located and detected using a CP electrical measuring instrument, which is a practical and efficient approach.

Magnetic Field-Assisted Interface Embedding Strategy to Construct 2D/3D Composite Structure for Stable Perovskite Solar Cells with Efficiency Over 24.

Perovskite solar cells (PSCs) based on 2D/3D composite structure have shown enormous potential to combine high efficiency of 3D perovskite with high stability of 2D perovskite. However, there are still substantial non-radiative losses produced from trap states at grain boundaries or on the surface of conventional 2D/3D composite structure perovskite film, which limits device performance and stability. In this work, a multifunctional magnetic field-assisted interfacial embedding strategy is developed to construct 2D/3D composite structure. The composite structure not only improves crystallinity and passivates defects of perovskite layer, but also can efficiently promote vertical hole transport and provide lateral barrier effect. Meanwhile, the composite structure also forms a good surface and internal encapsulation of 3D perovskite to inhibit water diffusion. As a result, the multifunctional effect effectively improves open-circuit voltage and fill factor, reaching maximum values of 1.246V and 81.36%, respectively, and finally achieves power conversion efficiency (PCE) of 24.21%. The unencapsulated devices also demonstrate highly improved long-term stability and humidity stability. Furthermore, an augmented performance of 21.23% is achieved, which is the highest PCE of flexible device based on 2D/3D composite perovskite films coupled with the best mechanical stability due to the 2D/3D alternating structure.

A suggested nanoscale partially depleted SOI-MOSFET (PDSOI) by built-in tunneling diodes- improvement on short channel effects and frequency features

This paper describes a new modified structure based on partially depleted silicon-on-insulator (PDSOI) MOSFETs with built-in tunneling diodes inside the buried oxide. This action will change the electric field and create a new path for the accumulated holes to be evacuated. Hence, the floating body effect (FBE), which is a very harmful event, is successfully controlled by these built-in diodes. The diodes will be formed by inserting N+ and P+ doping regions inside the buried oxide, which will provide both vertical and lateral holes for current tunneling through the channel region. Furthermore, with the introduction of the tunneling diode inside the buried oxide, the effective thermal conduction of the proposed device increases, eventually resulting in a reduction of the self-heating effect. Two parameters in the cases of reduced self-heating effect and FBE gave the suggested structure a potent capability to gain further figure of merits in the terms of subthreshold swing, leakage current, ION/IOFF, drain-induced barrier lowering (DIBL), power gains, drain-source conductance, cut-off frequency, and minimum noise figure. The device has been simulated by the ATLAS tools from the SILVACO family and compared with the conventional structure. All the obtained results displayed the privilege of the proposed device as compared to the common device.