Device Components Research Articles

Growth-based monolithic 3D integration of single-crystal 2D semiconductors.

The demand for the three-dimensional (3D) integration of electronic components is steadily increasing. Despite substantial processing challenges, the through-silicon-via (TSV) technique emerges as the only viable method for integrating single-crystalline device components in a 3D format1,2. Although monolithic 3D (M3D) integration schemes show promise3, the seamless connection of single-crystalline semiconductors without intervening wafers has yet to be demonstrated. This challenge arises from the inherent difficulty of growing single crystals on amorphous or polycrystalline surfaces after the back-end-of-the-line process at low temperatures to preserve the underlying circuitry. Consequently, a practical growth-based solution for M3D of single crystals remains unknown. Here we present a method for growing single-crystalline channel materials, specifically composed of transition metal dichalcogenides, on amorphous and polycrystalline surfaces at temperatures low enough to preserve the underlying electronic components. Building on this developed technique, we demonstrate the seamless monolithic integration of vertical single-crystalline logic transistor arrays. This accomplishment leads to the development of unprecedented vertical complementary metal oxide semiconductor (CMOS) arrays composed of grown single-crystalline channels. Ultimately, this achievement provides opportunities for M3D integration of various electronic hardware in the form of single crystals.

High-Performance Green and Blue Light-Emitting Diodes Enabled by CdZnSe/ZnS Core/Shell Colloidal Quantum Wells.

The unique anisotropic properties of colloidal quantum wells (CQWs) make them highly promising as components in nanocrystal-based devices. However, the limited performance of green and blue light-emitting diodes (LEDs) based on CQWs has impeded their practical applications. In this study, alloy CdZnSe core CQWs with precise compositions are tailored via direct cation exchange (CE) from CdSe CQWs with specific size, shape, and crystal structure and utilized hot-injection shell (HIS) growth to synthesize CdZnSe/ZnS core/shell CQWs exhibiting exceptional optoelectronic characteristics. This approach enabled the successful fabrication green and blue LEDs manifesting superior performance compared to previously reported solution-processed CQW-LEDs. The devices demonstrated a remarkable peak external quantum efficiency (20.4% for green and 10.6% for blue), accompanied by a maximum brightness 347,683cd m-2 for green and 38,063cd m-2 for blue. The high-performance represents a significant advancement for nanocrystal-based light-emitting diodes (Nc-LEDs) incorporating anisotropic nanocrystals. This work provides a comprehensive synthesis strategy for enhancing the efficiency of Nc-LEDs utilizing anisotropic nanocrystals.

Lithium-Ion Battery Life Prediction Using Deep Transfer Learning

Lithium-ion batteries are critical components of various advanced devices, including electric vehicles, drones, and medical equipment. However, their performance degrades over time, and unexpected failures or discharges can lead to abrupt operational interruptions. Therefore, accurate prediction of the remaining useful life is essential to ensure device safety and reliability. Conventional RUL prediction methods typically rely on regression analysis, signal processing, and machine learning techniques to assess battery conditions such as charge/discharge cycles, voltage, temperature, and durability. Although effective, these approaches are constrained by their dependence on large amounts of labeled data and the necessity for complex feature engineering to capture battery physical characteristics. In this study, we propose an approach that employs deep transfer learning to address these limitations. By leveraging pretrained model weights, the proposed method significantly improves the efficiency and accuracy of RUL prediction even under limited training data conditions. Furthermore, we investigate the impact of external environmental factors and physical battery characteristics on RUL prediction precision, thereby contributing to a more robust and reliable prediction framework.

Analyzing the effects of reflections on optical diagnostics in the main chamber and divertor of WEST (invited).

Understanding the erosion of plasma facing components in fusion devices is vital, particularly for long-pulse operations. This study presents the application of synthetic optical diagnosis on the all-W WEST tokamak. The analysis reveals reflections as significant contributors to measured emission, varying across main chamber limiters and divertor targets. Reflections at divertor locations can be up to 50% of measured emission while 95% at limiter locations. Oxygen is investigated as a proxy for low-Z species and underscores the importance of reflections in interpreting optical diagnostics, especially for validating plasma-material interactions and scrape-off layer impurity transport codes. As more fusion devices adopt full metal walls, the accurate assessment of reflections will become increasingly crucial for erosion analysis and plasma control.

Energetics and Raman spectroscopy of organic molecules encapsulated in single-walled boron nitride nanotubes: The example of π-conjugated oligothiophenes

The instability of organic electronic devices under environmental conditions narrowly related to the unstable aggregate state of organic semiconductors is one key obstacle to practical application. Herein, we highlight a promising strategy to overcome these drawbacks consisting to make use of the hollow space within single-walled boron nitride nanotubes (SWBNNTs). As a prototypical system of organic π-conjugated molecules encapsulated in SWBNNTs, we investigate the energetic stability and Raman spectra of a series of oligothiophene molecules (nT) (n = 2, 4, and 6) inside SWBNNTs through a combination of molecular dynamics (MD), density functional theory (DFT), bond polarisability model (BPM), and spectral moments method (SMM). The structural stability of these nanohybrids are explored initially. The optimal SWBNNTs diameters in which the resulting nanohybrids are stable with either one molecule (nT@SWBNNTs) and two encapsulated molecular chains (nT-nT@SWBNNTs) are computed. Then, the computed Raman spectra of the oligothiophenes and SWBNNTs before and after filling are reported. The energetic stability and the possible appearance or not of charge transfer in such nanohybrids are investigated by attentive analysis of the nanoconfinement effect on Raman features of oligothiophenes and SWBNNTs. The present results provide benchmark theoretical data to efficiently probe the interactions subsisting in such nanohybrids based on SWBNNTs templates that can serve as a new stable component for organic electronic devices.

Reflow oven with Wi-Fi connectivity

Abstract This paper will address a theme that highlights the role of an electrical equipment in the electrical industry, focusing on the process of soldering components onto the surface of printed circuit boards. The choice of the theme “Reflow Oven with Wi-Fi Connectivity” was driven by the desire to create a system with practical and applicative outcomes. The aim is to develop equipment that facilitates the soldering process of Surface Mounted Device (SMD) components. Such an automated system is valuable in the production of small batches of equipment, such as electronic modules for prototypes or various applications. The equipment or electronic module aims to depict a Printed Circuit Board (PCB) on which both Surface Mounted Devices (SMD) and Through Hole Technology (THT) components are mounted. Throughout the paper, the implementation of an automated system capable of carrying out the soldering process for SMD components will be discussed.

Modal Matching of Key Components in the Launching System Based on Response Surface Method

This chapter adopts Response Surface Methodology (RSM) combined with dynamic simulation and statistical analysis to deeply investigate the impact of modal matching of the inherent frequencies of key components of the launching system on the disturbances at the launch box opening during firing. Through experimental design, a polynomial fitting response surface model is established between design parameters and response objectives. The ultimate goal is to find the optimal design scheme that minimizes the initial disturbance, thereby achieving effective modal matching between the main components of the launching device. This research aims to provide a theoretical basis for improving firing accuracy and system stability.

Effect of gamma-rays irradiation on wettability of sol–gel silica nanofilms

Silica nanofilms are often used as antireflection films due to their unique optical properties. In the national high-power laser systems, in order to reduce optical reflection, the silica films are covered on the final optical components. However, the gamma radiation generated during the operation of these systems alters the properties of the silica films on the optical components. While wettability serves as the cornerstone of dust and pollution prevention in engineering technology, it has garnered limited attention in the research of optical components for high-power laser devices. Hence, this paper delves into the surface wettability and intricate hydrodynamics of droplets on silica films, both before and after gamma ray irradiation. The findings reveal that as the irradiation dose increases, the surface energy of the silica film rises, rendering it more lyophilic. By analyzing the impact dynamics of droplets on the silica thin film, we conclude that gamma irradiation renders the silica film coating on optical element surfaces more susceptible to contamination.

Design of non-fluorinated proton exchange membranes from Poly(Terphenyl fluorenyl isatin) with fluorene-linked sulfonate groups and microblock structures

Proton exchange membranes (PEMs) are essential components in energy storage and conversion devices, such as fuel cells and electrolyzers. In this study, we developed a series of non-fluorinated PEMs from poly (terphenyl fluorenyl isatin) with fluorene-pendent disulfonate groups. These polymers feature a microblock structure composed of hydrophobic blocks, hydrophilic blocks, and alternating blocks, arising from the differences in reactivity, concentration, and solubility between the hydrophobic p-terphenyl and hydrophilic disulfonated fluorene monomers. As a result, the sulfonic acid groups are unevenly distributed along the polymer chains, forming densely charged regions (IEC = 3.52 meq/g) with large ion clusters and lightly charged regions (IEC = 2.16 meq/g) with small ion clusters. This microstructure, combined with the degree of sulfonation, significantly influences the overall properties of the membranes, including robust mechanical strength (47.1–63.2 MPa), high thermal stability (up to 270 °C), low swelling ratio (18–25 % at 80 °C), and high proton conductivity (136–169 mS/cm in deionized water at 80 °C). The PFLSH60 membrane demonstrated comparable fuel cell performance to Nafion 212. Its hydrogen crossover current density was more than two times lower (0.86 mA/cm2 for PFLSH60 compared to 1.83 mA/cm2 for Nafion 212) under testing conditions of 80 °C and 100 % RH. This significantly reduced crossover improves fuel utilization in fuel cell stacks. This work offers valuable insights into the design of robust, high-performance PEMs by systematically analyzing the relationships between membrane structure, properties, and performance.

HEAT simulation and IR data comparison for ST40 plasma-facing components

The Heat Flux Engineering Analysis Toolkit (HEAT) (Looby et al., 2022) was used to simulate the heat flux, qtarget, on ST40 molybdenum divertors. Results were compared with experimental infrared (IR) data. Two shots, 11419 and 11376 at time instants 119 ms and 120 ms, with lower-biased disconnected double null geometries, were studied. Single-λ and multi-λ heat flux profiles were used as input in HEAT simulation. The simulated qtarget was used in OpenFOAM to calculate the corresponding temperature, T, on the divertors. Results showed that a good agreement on the simulated qtarget, T and shape of the heat flux on the divertor with the IR data was achieved when a multi-λ heat flux profile was used for 11419, and single-λ heat flux profile for 11376. This indicates that HEAT can be reliable in analyzing and understanding the heat loading of plasma facing components in tokamak devices.

Bilayer Boost to UV Assisted Supercapacitors: Enhanced Performance with Transparent TiO2/MoO3 Heterojunction Electrode

AbstractPhoto‐assisted supercapacitor is a promising smart device component for achieving both energy conversion and storage. The photo‐assisted functionality in a supercapacitor is realized through the choice of photo responsive electrode material under suitable illumination conditions. The well‐known electrochemically active electrode materials are wide band gap semiconductors which absorb strongly in UV light. However, most of the prior studies on photo‐assisted supercapacitors used visible light. Herein, we present a transparent TiO2/MoO3 bi‐layer heterojunction made by simple solution process as an efficient electrode for photo‐assisted supercapacitors under UV light illumination. The electrochemical performance of the electrode is significantly enhanced even with a less intense (0.05 mW/cm2) UV light, compared to dark as well as the single layer electrode under same illumination condition. The highest areal capacitance of 63.25 mF/cm2 at 0.1 mA/cm2 is achieved, that surpasses most of the recent relevant reports. The synergetic effect of UV illumination and the built‐in potential at the type II heterojunction interface encourages ion insertion and better collection of the photo‐generated carriers. The unique bi‐layer design also leads to better rate capability features. Thus, the work presents a new prospect for the development of transparent energy storage devices to be used in future smart technologies.

Broad Range Tuning of InAs Quantum Dot Emission for Nanophotonic Devices in the Telecommunication Bands.

InAs semiconductor quantum dots (QDs) emitting in the near-infrared are promising platforms for on-demand single-photon sources and spin-photon interfaces. However, the realization of quantum-photonic nanodevices emitting in the telecom windows with similar performance remains an open challenge. In particular, nanophotonic devices incorporating quantum light emitting diodes in the telecom C-band based on GaAs substrates are still lacking due to the relaxation of the lattice constant along the InGaAs graded layer which makes the implementation of electrically contacted devices challenging. Here, we report an optimized heterostructure design for QDs emitting in the telecom O- and C-bands grown by means of molecular beam epitaxy. The InAs QDs are embedded in mostly relaxed InGaAs matrices with fixed indium content grown on top of compositionally graded InGaAs buffers. Reciprocal space maps of the indium profiles and optical absorption spectra are used to optimize In0.22Ga0.78As and In0.30Ga0.70As matrices, accounting for the chosen indium grading profile. This approach results in a tunable QD photoluminescence (PL) emission from 1200 up to 1600 nm. Power and polarization dependent micro-PL measurements performed at 4 K reveal exciton-biexciton complexes from quantum dots emitting in the telecom O- and C-bands. The presented study establishes a flexible platform that can be an essential component for advanced photonic devices based on InAs/GaAs that serve as building blocks for future quantum networks.

A facile approach for fabricating efficient and stable perovskite solar cells.

Perovskite solar cells (PSCs) with high power conversion efficiencies (PCEs) can be produced using a variety of methods, such as different fabrication methods, device layout modification, and component and interface engineering. The efficiency of a perovskite solar cell is largely dependent on the overall quality of the perovskite thin-film in every scenario. The utilization of spin-coating followed by the antisolvent pouring (ASP) method is prevalent in nearly all fabrication techniques to achieve superior perovskite thin-films. Nevertheless, there are a few guidelines that must be followed precisely when using the ASP approach, including the antisolvent amount, duration, and area for dropping. The aforementioned challenging and necessary strategies frequently result in perovskite thin-films with pinholes, tiny grains, and broad grain boundaries, which impair the performance of PSCs. Therefore, the implementation of a straightforward approach that does not require the use of such complex ASP steps is crucial. Here, we employ a simple process that involves the hot-dipping of lead iodide (PbI2) thin-films in a hot solution of methylammonium iodide (MAI) and formamidinium iodide (FAI) in isopropanol (IPA) to produce high-quality perovskite thin-films. As the time required for the desired perovskite to crystallize is critical, we carefully examined various hot-dipping process times, such as 10 seconds, 20 seconds, 30 seconds, and 40 seconds. These time intervals yielded thin-films, which were named PSK-10, PSK-20, PSK-30, and PSK-40, respectively. Morphological and optoelectronic characterization demonstrated the high quality of the perovskite thin-films obtained through dipping PbI2 for 30 seconds. Consequently, the PSK-30-based PSCs produced higher PCEs of up to 21.52% compared to those of the ASP-based devices (20.79%). Furthermore, the unsealed PSCs prepared with PSK-30 and ASP were assessed for 252 hours at 25 °C and 40-45% relative humidity in order to determine their operational stability. The ASP-based device showed poor stability, retaining only 10% of its original PCE, whereas the PSK-30-based device retained 70% of its initial PCE. These results offer a new and viable approach for producing highly efficient and stable PSCs.

Energy systems and green sourced nanomaterials—A today’s outlook

Owing to current growing demands of environmental friendly energy devices, innumerable green materials/nanomaterials have been applied to design the desired high tech devices. Amongst energy devices, supercapacitors have been ranked distinctively for efficient energy storage competence. Principally, green nanocomposites derived from green or ecological polymers and green nanoparticles have been scrutinized for supercapacitor components. Concerning this, current review has been planned to sketch the energy storage application of green nanocomposites, predominantly for supercapacitors. In this concern, mostly synthetic green polymers (such as polyaniline, polypyrrole, etc.) and their blends with natural polymers (like chitosan) having fine biodegradability, non-toxicity, low cost, and superior device end performance have been found as the noteworthy materials. Additionally, green nanofillers like carbon nanoparticles (carbon nanotube, graphene, etc.) and metal nanoparticles have been processed with green polymers via ecological techniques, like in situ, solution, sonication, mixing, hydrothermal, exfoliation, reduction, etc., to form the anticipated energy device components. In consequence, the designed ecological nanocomposites expectedly had the advantages of low price/weight, superior mechanical/heat resilience, electron transference, capacitance, power/charge density, charge-discharge, sustainability as well as environmentally friendliness for energy related methodological systems. Incidentally, the design and performance challenges towards the application of ecological nanocomposites in energy storage devices have been conversed.

The application study of harmonization code in medical device adverse event reporting

BackgroundThe reporting of adverse events in medical devices (MD) is a starting point of post-market surveillance and the most common source of initial safety signals. Because MD adverse events (AE) occur globally and involve high-profile international public health crises, international regulators implanted standard codes for MDAE reporting. This study aimed to assess the application of MDAE terminology and codes by providing examples of virtual events.MethodsAn online survey was conducted among participants of the MD Training Program for Regulatory Authorities which provide International Medical Device Regulators Forum (IMDRF) adverse event terminology and codes, and six virtual MDAE cases.ResultsAll 29 of the 72 participants were regulators. In all cases, most participants selected the broad (level 1) codes rather than the detailed (level 2 or level 3) codes. While responders selected a variety of codes for all annexes in case 1, over 50% of responders selected the intended codes in case 6. The codes for cause investigation were chosen more frequently than other annexes for device problem, components, and health effect. No differences were observed in code selection amongst different stakeholders.ConclusionsWe identified the diversification in terminology and code selection for reporting MDAEs.

MDD-DETR: Lightweight Detection Algorithm for Printed Circuit Board Minor Defects

PCBs (printed circuit boards) are the core components of modern electronic devices, and inspecting them for defects will have a direct impact on the performance, reliability and cost of the product. However, the performance of current detection algorithms in identifying minor PCB defects (e.g., mouse bite and spur) still requires improvement. This paper presents the MDD-DETR algorithm for detecting minor defects in PCBs. The backbone network, MDDNet, is used to efficiently extract features while significantly reducing the number of parameters. Simultaneously, the HiLo attention mechanism captures both high- and low-frequency features, transmitting a broader range of gradient information to the neck. Additionally, the proposed SOEP neck network effectively fuses scale features, particularly those rich in small targets, while INM-IoU loss function optimization enables more effective distinction between defects and background, further improving detection accuracy. Experimental results on the PCB_DATASET show that MDD-DETR achieves a 99.3% mAP, outperforming RT-DETR by 2.0% and reducing parameters by 32.3%, thus effectively addressing the challenges of detecting minor PCB defects.

The charge transport properties of dicyanomethylene-functionalised violanthrone derivatives.

The study of organic small molecule semiconductor materials as active components of organic electronic devices continues to attract considerable attention due to the range of advantages these molecules can offer. Here, we report the synthesis of three dicyanomethylene-functionalised violanthrone derivatives (3a, 3b and 3c) featuring different alkyl substituents. It is found that the introduction of the electron-deficient dicyanomethylene groups significantly improves the optical absorption compared to their previously reported precursors 2a-c. All compounds are p-type semiconductors with low HOMO-LUMO gaps (≈1.25 eV). The hole mobilities, measured from fabricated organic field-effect transistors, range from 3.6 × 10-6 to 1.0 × 10-2 cm2 V-1 s-1. We found that the compounds featuring linear alkyl chains (3b and 3c) displayed a higher mobility compared to the one with branched alkyl chains, 3a. This could be the result of the more highly disordered packing arrangement of this molecule in the solid state, induced by the branched side chains that hinder the formation of π-π stacking interactions. The influence of dicyanomethylene groups on the charge transport properties was most clearly observed in compound 3b which has a 60-fold improvement in mobility compared to 2b. This study demonstrates that the choice of the solubilising group has a profound effect on the hole mobility on these organic semiconductors.

Excellent energy storage performance of multi-alternating-layer structured PMMA/PVDF dielectric composite at high-temperature

Polymer dielectric capacitors have high power density and are an integral component of electronic and power device. Currently, the limited energy density restricts their further application. In this research, a novel method was designed to optimize performance of PMMA/PVDF composite via an alternating stacked multi-layer structure. And, the five-alternating-layer of PVDF-PMMA-PVDF-PMMA-PVDF (F-A-F-A-F) composite has excellent dielectric properties, for instance, a better dielectric constant (4.52@1 kHz) and a low dielectric loss (0.034@1 kHz). The discharge energy density (Ue) of it is significantly larger than that of PMMA and PVDF. Particularly, the Ue of F-A-F-A-F composite is increased by 83.0 % (from 4.71 J/cm3 to 8.62 J/cm3) with charging-discharging efficiency of 60 % at 80 °C. Moreover, the F-A-F-A-F composite achieves an excellent stability after 40,000 cycles. This composite has a wide range of potential applications in the field of traditional dielectric capacitor due to its good energy storage performance and cycle stability.

Development of a device for assessment of aortic root parameters and positioning of aortic valve cusps during aortic valve-sparing root replacement

Background. A promising method of surgical treatment of aneurysms of the root and ascending aorta (AA) with unchanged aortic valve (AV) cusps is aortic valve-sparing root replacement (VSRR) with AV reimplantation (David procedure). To date, there are no clear indications to make a choice in favor of valve-replacing or valve-sparing intervention. The result of visual evaluation and the choice of treatment method based on the surgeon’s experience remains the main criteria. Objective. In the experiment to develop a prototype and method of application of the device for positioning of AV cusps, which will simplify and standardize aortic valve-sparing root replacement, improve the results and increase the reproducibility of these operations. Design and methods. Three-dimensional (3D) modeling of the device components was performed in the parametric open-source computer-aided design environment FreeCAD 0.20.1. Two-dimensional sketches were converted into three-dimensional models and exported as stl files for 3D printing. Solid components of the model were made of polylactic acid (PLA-plastic), elastic components were made of rubber-like photopolymer (Dropstil F556 10 shore A) also by 3D printing using SLA technology. Results. The device consists of 2 similar ring-sizers of variable diameter connected by three struts of variable length. In the upper part of each of the struts fastenings to the distal ring represents T-shaped cutouts for temporary locking of the suture-holders passed through the commissures of the AV cusps. For proximal locking of the aortic graft and the proximal ring-sizer, 3 U-shaped sutures are used, passed from inside to outside through the AV ring, the proximal part of the graft and taken in the tourniquets. The diameters of the ring-sizers can be varied between 25–40 mm by rotating a worm drive. A graft is placed on the inner side of the device, the suture-holders attached to the tops of the commissures are locked in the T-shaped notches in the upper parts of the struts. The device will allow changing the position of the coaptation point, coaptation square and performing hydraulic tests in different positions of the cusps, as well as variable diameters at the level of the AV ring and sinotubular junction (25–40 mm). When the target position of the coaptation point, coaptation area and satisfactory hydraulic test result are achieved, the cusps with commissures are locked inside the graft and the device is removed. Conclusion. A new device has been developed to facilitate, reproduce, and standardize VSRR. The results obtained will facilitate and accelerate the performance of VSRR, increase the reproducibility of the technique, and reduce the risks of complications.

Chemical Recycling of Epoxy Thermosets: From Sources to Wastes

As one of the most widely used thermosets due to its excellent performances, epoxy resin (EP) is widely used in various fields and often employed as a component of composite actuator devices, strengthening their mechanical properties. However, the expanding production of EP inevitably leads to the accumulation of waste end-of-life equipment and the corresponding increasingly serious environmental problems. This review summarizes the recycling strategies of EP, divided into two perspectives: recycling from wastes and sources. Chemical recycling is expected to be the future of waste EP treatment, and we discuss the chemical recycling methods of existing waste EP based on different mechanisms, including the selective cleavage of ester bonds, C–N bonds, and C–O bonds. On the other hand, epoxy vitrimer networks based on various dynamic covalent linkages are also outlined, which can respond to multiple external stimuli and provide materials with recyclability from the origin. Therefore, the use of epoxy vitrimer actuators can prevent waste generation throughout the whole lifecycle. We present some issues of concern in both waste-based and source-based recycling strategies and emphasize the significance of scaling-up. Finally, we summarized the current situation and present some future perspectives with the aim of making practical contributions to environmental issues.