Design Of Devices Research Articles

Joint impact of self-heating effect and lattice stress on the design performance of Si1−xGex FinFET with advanced process integration

Abstract In advanced FinFET process simulations, a strong correlation exists between the stress induction mechanism and the severe self-heating effect (SHE). These two factors are interrelated, and their interaction further diminishes the thermal conductivity of the device. This article employs computer-aided design for three-dimensional simulations and introduces a process-oriented simulation method. We investigate the influence of various stress sources including lattice stress, channel stress, stress relaxation buffer (SRB), and source/drain (S/D) extrapolation stress on FinFET performance in different directions under self-heating conditions, specifically analyzing silicon germanium (SiGe) and germanium-based FinFET. The results indicate that, under the influence of SHE, the y–y direction stress in the device channel increases by nearly 600 MPa. Self-heating significantly affects stress distribution within the device; in simulations of germanium-based devices, the inferior intrinsic material properties and thermal conductivity of pure germanium result in a maximum lattice temperature that is substantially higher than that of pure silicon devices. The impact of SHE and lattice stress on the performance of advanced FinFET is explored, revealing that the coupling effect of self-heating and lattice stress has a profound influence on device design performance.

A user-centered approach in complex engineering design environments

In complex engineering design environments, the demand for high quality products and high functionality are critical, the end-user requirements have to be integrated into the design process since the earliest design stages. In such contexts, strict design requirements related to quality, safety, and usability must be taken into account concurrently. To this aim, in this work, an integrated user-centered decision-based design method is proposed in the medical design environment context. This work is aimed at proposing a design method to be applied to complex design environments. The proposed case study is the design of an intercom device, aimed at improving patient-doctor communication in the case of bedridden patients on with helmet for Continuous Positive Airway Pressure (CPAP) therapy during SARS- CoV2 pandemic emergency. Patients undergoing helmet-assisted ventilation are often immersed in a highly noisy environment, unable to fully communicate their needs to the doctors. A three-steps decision based integrated product design and process simulation are used in the early design stages, to gain optimal product designs in a user-centered design viewpoint, for novel industrial products. The first step, modular design, is aimed at defining relations between the components of the assembly in a user centered approach. Design alternatives are generated in a Design for Manufacturing and Assembly DFMA viewpoint. In the second step, the group decision making step, in a multiple criteria context, the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) is applied together with the fuzzy set theory, to overcome uncertainties in the verbal judgments of the decision makers. The third step is related to the simulation of the assembly and manufacturing process, with the aim of defining a final optimal design. The proposed group multicriteria decision making based design method proved to be efficient in complex user centered engineering design contexts.

Spin polarisation and non-isotropic effective mass in the conduction band of GdN

GdN is a ferromagnetic semiconductor which has seen increasing interest in the preceding decades particularly in the areas of spin- and superconducting- based electronics. Here we report a detailed computational and optical spectroscopy study of the electronic structure of stoichiometric and nitrogen vacancy doped GdN. Based on our calculations we provide the effective mass tensor for undoped GdN, and some indicative values for electron doped GdN. Such a property is valuable as it can affect device design, and can be measured experimentally to validate the existing computation results.

Reconfigurable skyrmion logic gates and diodes in the same synthetic antiferromagnetic nanotrack based on potential well inducting effect

Abstract Magnetic skyrmions are nanoscale spin configurations with topological protection properties, which have broad application potential in the next generation of spintronic devices. Here, we report on the current-driven dynamics of skyrmions in synthetic antiferromagnetic nanotracks with voltage-controlled magnetic anisotropy. This research reveals that, compared to a single skyrmion, when two skyrmions are createdsimultaneously, the inducting effect of the potential well generated by the voltage gateon the skyrmions is partially counteracted by the interaction between the skyrmions,resulting in a reduction in the critical current required for the skyrmions to pass thevoltage gate. Moreover, the critical current required for the forward moving skyrmions to depin from the voltage gate is significantly lower than that required for the reverse moving skyrmions. Based on the dynamic behavior of skyrmions, we have proposed and achieved the skyrmion logic AND, OR, NOT, NAND, NOR gates and the diodes on the same synthetic antiferromagnetic nanotrack by micromagnetic simulation, in which the logic NOT, NAND, and NOR gates are realized in a reconfigurable way. Our results are beneficial for the design and development of non-volatile spintronic devices with integrated multifunctionality and ultra-low energy consumption.

What hepatology clinicians and their patients with alcohol-related liver disease think of wearable alcohol biosensors to aid abstinence from alcohol: A qualitative study.

We aimed to determine acceptability and feasibility of innovative wearable alcohol biosensor monitors (ABM) for patients with alcohol-related liver disease (ALD) and their clinicians. Patients and clinicians at a tertiary care centre participated in qualitative interviews on usability, acceptability, feasibility, efficiency/effectiveness, impact of device on behaviour/clinical practice and preferences/barriers. Interviews were audiotaped, transcribed and coded using a constant comparison method for category themes. Patients (n = 23) were 56% female, mean 44 years old, 87% White, with moderate-severe liver disease. Some felt the ABMs appearance was unappealing; others felt it provided an opportunity for openness and education of others. While some found it feasible to wear, others felt it was unrealistic to wear 24/7. Importantly, there were many positive themes on effectiveness/efficiency-participants felt the ABM could better record their alcohol use and patterns of use than they could remember. Patients felt wearing the ABM motivated abstinence, gave accountability and was a source of security. Clinicians (n = 13) were mostly hepatologists (77%), seeing on average 38 ALD patients/month. Clinicians felt seeing patterns and amounts of alcohol use could inform clinical decision making and treatments but expressed concern over the volume and complexity of data. Perspectives on ABMs for managing ALD were mixed among patients and providers. Future device designs may overcome acceptability barriers due to device appearance. However, for clinicians, the logistics of data gathering plus the complexity and volume of data produced by the ABM device requires considerable thought to make this an efficient tool for clinical use. gov identifier NCT03533660: Alcohol biosensor monitoring for alcohol liver disease.

Sustainable Silk Fibroin Ionic Touch Screens for Flexible Biodegradable Electronics with Integrated AI and IoT Functionality.

The increasing prevalence of electronic devices has led to a significant rise in electronic waste (e-waste), necessitating the development of sustainable materials for flexible electronics. In this study, silk fibroin ionic touch screen (SFITS) is introduced, a new platform integrating natural silk fibroin (SF) with ionic conductors to create highly elastic, environmentally stable, and multifunctional touch interfaces. Through a humidity-induced crystallization strategy, the molecular structure of SF is precisely controlled to achieve a balanced combination of mechanical strength, electrical conductivity, and biodegradability. The assembly and operational reliability of SFITS are demonstrated under various environmental conditions, along with their reusability through green recycling methods. Additionally, the intelligent design and application of SFITS are explored by incorporating Internet of Things (IoT) and artificial intelligence (AI) technologies. This integration enables real-time touch sensing, handwriting recognition, and advanced human-computer interactions. The versatility of SFITS is further exemplified through applications in remote control systems, molecular model generation, and virtual reality interfaces. The findings highlight the potential of sustainable ionic conductors in next-generation flexible electronics, offering a path toward greener and more intelligent device designs.

Molecular Dynamics Simulations in Nanoscale Heat Transfer: A Mini Review

Abstract As device miniaturization advances, managing heat at the nanoscale becomes increasingly critical. Nanoscale heat transfer presents unique challenges, including size effect, ballistic transport, and complex phonon interactions, which conventional macroscopic theories cannot fully address. Molecular dynamics (MD) simulations have been a powerful tool for directly modeling atomistic motion and interactions, offering valuable insights into thermal phenomena. This article provides an overview of MD methods and their contributions to understanding thermal transport in inorganic crystals, amorphous solids, polymers, and interfaces. Additionally, we offer our perspective on the emerging trends and future research directions in MD simulations, emphasizing their potential to unravel complex thermal phenomena and guide the design of next-generation thermal materials and devices.

Inverse Size-Scaling Ferroelectricity in Centrosymmetric Insulating Perovskite Oxide DyScO3.

The breaking of inversion symmetry dictates the emergence of electric polarization, whose topological states in superlattices and bulks have received tremendous attention for their intriguing physics brought for novel device design. However, as for substrate oxides such as LaAlO3, KTaO3, RScO3 (R = rare earth element), their centrosymmetric trivial attributes make their functionality poorly explored. Here, the discovery of nanoscale thickness gradient-induced nonpolar-to-polar phase transition in band insulator DyScO3 is reported by using atomic resolution transmission electron microscopy. As the free-standing specimen reduces to a critical thickness ≈5 nm, its inversion symmetry is spontaneously broken by surface charge transfer, which gives rise to asymmetric Dy atomic displacements and ferrodistortive octahedral order, as substantiated by the first-principles calculations. Apart from the observation of migratable polar vortex structures, the switchable electric polarization by applied electric field is demonstrated by the piezoresponse force microscopy experiments. Given the decisive role of critical size in generating ferroelectricity, a concept of "inverse size-scaling ferroelectric" is proposed to define a class of such materials. Distinct from the proper and improper ferroelectrics, the findings offer a new platform to explore novel low-dimensional ferroelectrics and device applications in the future.

A Study on Position and Lumen Geometry at the Origin of External Carotid Artery in Human Adult Cadavers

Background: External carotid artery is the predominant source of blood supply to the structures in the head and neck region. Morphological anomalies in the external and internal carotid arteries may lead to severe complications, when radiographic evaluations and surgical proceedings are done in the neck without any prior knowledge. Normal arterial diameters of external carotid arteries were important in-patient selection, preoperative planning, and design of new endovascular devices for arterial reconstruction. Material and Methods: A descriptive study was performed on 60 formalin fixed male and female Human adult cadavers, aged between 45 to 75 yrs in the department of Anatomy, Dr.Pinnamaneni Siddhartha Institute of Medical Sciences and Research foundation, chinoutapalli and Mamatha academy of medical sciences, Hyderabad , during the academic years, 2018- 2023 during the academic years . Observations from both right and left external carotid arteries (total- 120 sides) were noted. Results: In the present study, positions of external carotid artery observed were, antero-medial in 90%, anterolateral in 6.66% and lateral position in 3.33% of cases. The mean ± standard deviation calculated for the diameter of lumen at the origin of external carotid artery on the right side was 0.623±0.048 cm and on the left side was 0.608±0.050cm. For both right and left sides was 0.616±0.049cm. Conclusion: Positional variations of external carotid artery observed in the present study were anterolateral and lateral positions. In such cases Carotid endarterectomy can be safely done, after transposing the internal carotid artery to normal location. Data on normal arterial diameters were helpful during reconstructive surgeries and manufacture of endovascular devices, respective to different ethnic groups. KEYWORDS: Common Carotid Artery, Carotid Artery External, Positional Variations, Lumen Geometry, Carotid Endarterectomy.

Probing the limits and capabilities of diffusion models for the anatomic editing of digital twins

Numerical simulations of cardiovascular device deployment within digital twins of patient-specific anatomy can expedite and de-risk the device design process. Nonetheless, the exclusive use of patient-specific data constrains the anatomic variability that can be explored. We study how Latent Diffusion Models (LDMs) can edit digital twins to create digital siblings. Siblings can serve as the basis for comparative simulations, which can reveal how subtle anatomic variations impact device deployment, and augment virtual cohorts for improved device assessment. Using a case example centered on cardiac anatomy, we study various methods to generate digital siblings. We specifically introduce anatomic variation at different spatial scales or within localized regions, demonstrating the existence of bias toward common anatomic features. We furthermore leverage this bias for virtual cohort augmentation through selective editing, addressing issues related to dataset imbalance and diversity. Our framework delineates the capabilities of diffusion models in synthesizing anatomic variation for numerical simulation studies.

Amorphous Magnesium Coating for Achieving Functional Changes from Antibacterial to Osteogenic Activities.

Medical devices composed of titanium (Ti) should exhibit antibacterial and osteogenic activities to achieve both infection prevention and rapid bone reconstruction. Here, a Ti surface was modified by performing magnetron sputtering (MS) using pure Mg or Mg-30Ca alloy targets for surface functionalization. MC0, prepared with a pure Mg target, had a crystalline metallic-Mg coating layer, whereas MC30, prepared with an Mg-30Ca alloy target, had an amorphous coating composed of Mg and Ca. Both samples rapidly dissolved when immersed in a cell culture medium and exhibited antibacterial activities against methicillin-resistant Staphylococcus aureus and cytotoxicity against MC3T3-E1 cells. Furthermore, MC30 promoted the proliferation and calcification of MC3T3-E1 cells because of the subsequent deposition of calcite on the surface after rapid dissolution. Our findings are the first to reveal that MS performed by using an Mg-30Ca alloy target endowed Ti surfaces with functional changes from antibacterial to osteogenic activities over time. Our results provide fundamental insights into the surface design of Ti-based medical devices for enhanced bone reconstruction and infection prevention and offer possibilities for biomedical applications of Mg-based coatings.

The Role of Aesthetics in Medical Device Design

This paper examines the importance of aesthetics in the design of medical devices, examining how aesthetic considerations contribute to improved usability, patient acceptance, and emotional well-being. Medical device manufacturers have increasingly integrated aesthetic elements that go beyond functionality to foster a personal connection between devices and users. The incorporation of aesthetic design promotes psychological comfort, enhances trust, and facilitates a sense of satisfaction, particularly in devices intended for long-term use. By analyzing various case studies and examining current methods of quantifying aesthetic factors in medical devices, this study reveals the implications of aesthetics on device effectiveness and user compliance. The paper argues that while aesthetic value in medical devices is subjective, its impact on user experience and operational success is substantial. Finally, challenges related to regulatory standards, cultural diversity, and the balance between form and function are discussed, underscoring the need for an interdisciplinary approach to creating aesthetically mindful medical devices. Keywords: Aesthetic Design, Medical Device Usability, Patient Compliance, Emotional Well-being, User Experience, Product Acceptance.

PROTOTYPE MANUFACTURING OF A NEW DYNAMIC-BASED PRESSURE MEASUREMENT TEST DEVICE FOR MEDICAL AND TEXTILE APPLICATIONS

Customers nowadays demand that their clothes be comfortable and suitable for their health in addition to the aesthetic features of the clothes they wear. Therefore, manufacturers following technological innovations to test their product capability are putting those devices on the market to measure the impact on health. The study describes the design, development, and prototype manufacturing stages of a new pressure measurement test device for measuring the pressure resulting from the interaction of human legs and stretch garments. The device can bend from the knee and move dynamically which has innovative aspects compared to the ones commercially available. After mass production of the device, it might be possible to measure the pressure levels of the garments to the human body, therefore, the effects of the fabrics on blood pressure in addition to body physiology can be evaluated with concrete values.

Breaking the angular dispersion limit in thin film optics by ultra-strong light-matter coupling

Thin film interference is integral to modern photonics, e.g., allowing for precise design of high performance optical filters, photovoltaics and light-emitting devices. However, interference inevitably leads to a generally undesired change of spectral characteristics with angle. Here, we introduce a strategy to overcome this fundamental limit in optics by utilizing and tuning the exciton-polariton modes arising in ultra-strongly coupled microcavities. We demonstrate optical filters with narrow pass bands that shift by less than their half width (< 15 nm) even at extreme angles. By expanding this strategy to strong coupling with the photonic sidebands of dielectric multilayer stacks, we also obtain filters with high extinction ratios and up to 98% peak transmission. Finally, we apply this approach in flexible filters, organic photodiodes, and polarization-sensitive filtering. These results illustrate how strong coupling provides additional degrees of freedom in thin film optics that will enable exciting new applications in micro-optics, sensing, and biophotonics.

COMPLEX TECHNOLOGY OF THE CLEANING OF AGGLOMERATION GASES FROM DUST AND HARMFUL GASES WITH OBTAINING A GOOD PRODUCT

The purpose of the work is to improve the design of the dust-catching device of the sintering machine, to increase the efficiency of catching charged dust particles in laminar layers near the precipitating elements, the configuration and location of the elements of the precipitating elements, to establish the dependence of the effective (calculated) drift speed of charged dispersed particles on the speed of the medium being cleaned, with classical the process of electrogas purification and the combined flow of gases in electrofilters. It was established that the combined movement of gases in a modular unit ensures the charging of the entire population of dust particles to the limit values ​​by organizing a highly turbulent flow and keeping dust particles in the zones with the greatest tension in the corona charge covers, as well as effective trapping of charged dust particles in laminar layers near the precipitating elements . Mathematical modeling of the deposition block was carried out in order to optimize the configuration. The main dependences of the number and mutual location of precipitating elements to ensure maximum dust deposition were established. Studies of gas medium velocity spectra in models of new electrostatic precipitators have been carried out. The optimal live cross-sections of the aerodynamic partitions are determined to ensure favorable conditions for charging suspended particles and uniform distribution of the cleaned flow through the catching holes. The MV-2 modular type electric gas purification device with a capacity of 30 thousand nm3/h has been developed, based on innovative developments in the field of KEIT (combined electro-ion gas purification technology) in the field of conversion and control of cascade energy and aerodynamics of turbulent and laminar flows during inertial deposition dispersed suspension of flue gases. An apparatus for cleaning gases from a sinter machine with a capacity of up to 400,000 nm3/h is proposed. with an efficiency of 99 %, for replacing existing equipment (multicyclones). "MV-2JS" electric device was developed. This is a plasma-catalytic reactor, which allows you to produce the necessary amount of ozone in a low-cost way to oxidize the harmful components (SO2, NOx, CO) of the outgoing gases. The use of this device allows, in addition to the cleaning of flue gases from harmful gas impurities, to obtain commercial products (fertilizers, gypsum, sulfuric acid, etc.) at the output and to completely get rid of solid and liquid waste during gas desulfurization.

A performance evaluation of commercially available and 3D-printable prosthetic hands: a comparison using the anthropomorphic hand assessment protocol

Despite significant technological progress in prosthetic hands, a device with functionality akin to a biological extremity is far from realization. To better support the development of next-generation technologies, we investigated the grasping capabilities of clinically prescribable and commercially available (CPCA) prosthetic hands against those that are 3D-printed, which offer cost-effective and customizable solutions. Our investigation utilized the Anthropomorphic Hand Assessment Protocol (AHAP) as a benchtop evaluation of the multi-grasp performance of 3D-printed devices against CPCA prosthetic hands. Our comparison sample included three open-source 3D-printed prosthetic hands (HACKberry Hand, HANDi Hand, and BEAR PAW) and three CPCA prosthetic hands (Össur i-Limb Quantum, RSL Steeper BeBionic Hand V3, and Psyonic Ability Hand), along with including previously published AHAP data for four additional 3D-printed hands (Dextrus v2.0, IMMA, InMoov, and Limbitless). Our findings revealed a notable grasping performance disparity, with 3D-printed prostheses generally underperforming compared to their CPCA counterparts, specifically in cylindrical, diagonal volar, extension, and spherical grips. We propose that the observed performance shortfalls are likely attributed to the design or build quality of the 3D-printed prostheses, owing to the fact that 3D-printed hands often have a lower technology readiness level for widespread use. Addressing the limitations highlighted in this work and subsequent research will play a crucial role in refining the design and functionality of both 3D-printed and CPCA prosthetic devices.

Digital instrument simulator to optimize the development of hyperspectral systems: application for intraoperative functional brain mapping.

Intraoperative optical imaging is a localization technique for the functional areas of the human brain cortex during neurosurgical procedures. These areas can be assessed by monitoring cerebral hemodynamics and metabolism. Robust quantification of these biomarkers is complicated to perform during neurosurgery due to the critical context of the operating room. In actual devices, the inhomogeneities of the optical properties of the exposed brain cortex are poorly taken into consideration, which introduce quantification errors of biomarkers of brain functionality. Moreover, the best choice of spectral configuration is still based on an empirical approach. We propose a digital instrument simulator to optimize the development of hyperspectral systems for intraoperative brain mapping studies. This simulator can provide realistic modeling of the cerebral cortex and the identification of the optimal wavelengths to monitor cerebral hemodynamics (oxygenated and deoxygenated hemoglobin Hb) and metabolism (oxidized state of cytochromes and and cytochrome-c-oxidase oxCytb, oxCytc, and oxCCO). The digital instrument simulator is computed with white Monte Carlo simulations of a volume created from a real image of exposed cortex. We developed an optimization procedure based on a genetic algorithm to identify the best wavelength combinations in the visible and near-infrared range to quantify concentration changes in , Hb, oxCCO, and the oxidized state of cytochrome and (oxCytb and oxCytc). The digital instrument allows the modeling of intensity maps collected by a camera sensor as well as images of path length to take into account the inhomogeneities of the optical properties. The optimization procedure helps to identify the best wavelength combination of 18 wavelengths that reduces the quantification errors in , Hb, and oxCCO by 47%, 57%, and 57%, respectively, compared with the gold standard of 121 wavelengths between 780 and 900nm. The optimization procedure does not help to resolve changes in cytochrome and in a significant way but helps to better resolve oxCCO changes. We proposed a digital instrument simulator to optimize the development of hyperspectral systems for intraoperative brain mapping studies. This digital instrument simulator and this optimization framework could be used to optimize the design of hyperspectral imaging devices.

Analysis of electromagnetic force characteristics and wheelbase design of Maglev car based on double permanent magnet electrodynamic wheels

With the advantage of “suspension-drive” integration, the Maglev car has broad application prospects in fields, such as Maglev highways. Currently, a laboratory-scale Maglev car prototype has been built by one of the groups of Southwest Jiaotong University equipped with four permanent magnet electrodynamic wheels. A full-scale Maglev car is planned for design. The distance between the front and rear electrodynamic wheels (EDWs) of a Maglev car will directly affect the safety of the entire car system operation; therefore, it is necessary to explore the wheelbase design. This paper first analyzes the relationship between the electromagnetic force of double EDWs (DEDWs) and the wheelbase under the size of a scaled prototype through 3D simulation and verifies the effectiveness of the simulation model through experiments. Furthermore, the electromagnetic force characteristics of full-scale DEDWs were explored through finite element simulation methods. Finally, we provide the wheelbase design standards for the Maglev car of any size. The findings indicate that the electromagnetic force of DEDWs first rapidly decreases and then stabilizes with increasing wheelbase. The ratio of the inner and outer radius of the DEDWs, and the material and thickness of the conductor plate do not affect the critical value of the wheelbase, while the rotation speed and air gap of DEDWs are the parameters affecting the design of the wheelbase. This article provides a new idea for the wheelbase design of the Maglev car, which is expected to provide some reference for the structural design and parameter optimization of multi-EDW devices.

Periodic Burst Freezing in a Water-Filled Capillary Tube.

Water-filled porous structures are ubiquitous components in life sciences and engineering. At sufficiently low temperatures, the water inside the porous structures can freeze, triggering the frost heave effect and causing problems such as permafrost, frost damage, and frostbite. In this study, we report a unique pattern of frost heat release through periodic bulging and bursting at the end of a water column inside a capillary tube. When water freezes, it expands in volume and attempts to drain out. However, surface tension can hinder the flow of water, resulting in the formation of a bulge that periodically bursts when the spherical molecule reaches a critical threshold. We determined that the critical contact angle of the bulge is approximately 135°, which is balanced by the surface tension at the three-phase line of contact. The size of the bulge increases nonlinearly with the diameter of the capillary tube, while the number of periodic repetitions is inversely proportional to the tube diameter and directly proportional to the length of the water column. These findings provide insights into the interaction between surface tension and frost heave, which has important implications for the design and optimization of microfluidic devices with improved resistance to freezing.

A PINN framework for inverse physical design of metal-loaded electromagnetic devices

To solve the difficulty of inverse design of metal-loaded electromagnetic devices, we propose a physics-informed neural network (PINN) framework. With the emergence of PINNs, some scholars within the field of electromagnetism have utilized them to design dielectric-loaded electromagnetic devices. However, using PINN to design metal-loaded electromagnetic devices is still uncommon due to the difficulty of binarization of metal shapes. In light of this, we propose a PINN framework to address the inverse physical design of metal-loaded electromagnetic devices. In PINN, we embed mathematical-physics models into the network, which endows the training parameters of PINN with practical physical significance. The main innovation of this paper is to solve the binarization problem in the inverse design of metal-loaded devices within the PINN. To verify the feasibility of our method, we provide an example of designing a dual-layer metal diaphragm-loaded parallel plate waveguide device. The PINN presented with metal binarization in this paper offers a novel approach to the inverse physical design of metal-loaded electromagnetic devices.