Research

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16 pages, 10186 KiB

Open AccessArticle

A Study on Characteristic Mode Equations of Radiation Problems Contrasted with Scattering Problems for Dielectric Bodies

by Xingyue Guo, Dehua Kong, Renzun Lian, Yuanan Liu and Mingyao Xia

Electronics 2023, 12(3), 704; https://doi.org/10.3390/electronics12030704 - 31 Jan 2023

Cited by 1 | Viewed by 1074

Abstract

This paper is concerned with the extractions of electromagnetic characteristic modes (CMs) for lossless dielectric bodies, for which spurious modes are prone to generate using the traditional definition of CMs based on the Poggio–Miller–Chang–Harrington–Wu–Tsai (PMCHWT) equations. It is found that the impedance matrix [...] Read more.

This paper is concerned with the extractions of electromagnetic characteristic modes (CMs) for lossless dielectric bodies, for which spurious modes are prone to generate using the traditional definition of CMs based on the Poggio–Miller–Chang–Harrington–Wu–Tsai (PMCHWT) equations. It is found that the impedance matrix of PMCHWT equations cannot distinguish (i) which domain is the dielectric body and which domain is the background and (ii) from which domain the excitation source was applied. If the system is taken as a scattering problem, the spurious modes are solutions to a reverse media problem, i.e., exchanging the media of the dielectric body and the background space. However, if the system is taken as a radiation problem, no appropriate CMs that meet the specified boundary conditions are obtained. These phenomena indicate that CMs developed from scattering systems are not suitable for radiation systems. To clarify the issue, four cases with reverse media and with excitation sources in either domain are examined. The four cases are distinct in essence, but the PMCHWT equations cannot distinguish them. As a result, definitions of CMs for the four cases should be given along with their specific boundary conditions. Especially, the CMs for the radiation problems we consider here show that the excitation source inside the material object should be properly defined in order to be distinguished from scattering problems. Full article

(This article belongs to the Special Issue Recent Advancements and Applications of Computational Electromagnetics)

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18 pages, 6095 KiB

Open AccessArticle

A Hybrid Method of Adaptive Cross Approximation Algorithm and Chebyshev Approximation Technique for Fast Broadband BCS Prediction Applicable to Passive Radar Detection

by Xing Wang, Lin Chen, Fang Li, Chunheng Liu, Ying Liu, Zhou Xu and Hairong Zhang

Electronics 2023, 12(2), 295; https://doi.org/10.3390/electronics12020295 - 06 Jan 2023

Viewed by 1173

Abstract

A hybrid method combining the adaptive cross approximation method (ACA) and the Chebyshev approximation technique (CAT) is presented for fast wideband BCS prediction of arbitrary-shaped 3D targets based on non-cooperative radiation sources. The incident and scattering angles can be computed by using their [...] Read more.

A hybrid method combining the adaptive cross approximation method (ACA) and the Chebyshev approximation technique (CAT) is presented for fast wideband BCS prediction of arbitrary-shaped 3D targets based on non-cooperative radiation sources. The incident and scattering angles can be computed by using their longitudes, latitudes and altitudes according to the relative positions of the satellite, the target and the passive bistatic radar. The ACA technique can be employed to reduce the memory requirement and computation time by compressing the low-rank matrix blocks. By exploiting the CAT into ACA, it is only required to calculate the currents at several Chebyshev–Gauss frequency sampling points instead of direct point-by-point simulations. Moreover, a wider frequency band can be obtained by using the Maehly approximation. Three numerical examples are presented to validate the accuracy and efficiency of the hybrid ACA-CAT method. Full article

(This article belongs to the Special Issue Recent Advancements and Applications of Computational Electromagnetics)

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16 pages, 5054 KiB

Open AccessArticle

An Accelerated Time-Domain Iterative Physical Optics Method for Analyzing Electrically Large and Complex Targets

by Tai-Ping Sun, Zhou Cong, Zi He and Dazhi Ding

Electronics 2023, 12(1), 59; https://doi.org/10.3390/electronics12010059 - 23 Dec 2022

Cited by 2 | Viewed by 1242

Abstract

A local area coupling-based time-domain iterative physical optics (TD-LIPO) method for the analysis of the scattering from electrically large and complex targets is proposed in this study. A modulated Gaussian-pulse plane wave is taken as the incident wave. Initially, via a ray-tracing mechanism, [...] Read more.

A local area coupling-based time-domain iterative physical optics (TD-LIPO) method for the analysis of the scattering from electrically large and complex targets is proposed in this study. A modulated Gaussian-pulse plane wave is taken as the incident wave. Initially, via a ray-tracing mechanism, the current radiation iteration is limited to the local area, and the iteration times are determined by the bounce times. This approach can lower the enormous computation time. In addition, GPU parallel technology is also applied to accelerate the method. Finally, the TD-LIPO method is used to obtain the scattering echo data matrix of the target under different radar observation angles. An inverse fast Fourier transform (IFFT) is performed on the matrix to obtain the ISAR image under a small bandwidth and small angle. Numerical examples and ISAR images show that the accelerated local area coupling technique can significantly improve computational efficiency and verify feasibility in radar imaging. Full article

(This article belongs to the Special Issue Recent Advancements and Applications of Computational Electromagnetics)

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19 pages, 5603 KiB

Open AccessArticle

Global Scattering Center Representation of Target Wide-Angle Single Reflection/Diffraction Mechanisms Based on the Multiple Manifold Concept

by Jinwen Lu, Yanjin Zhang, Hua Yan, Lei Zhang and Hongcheng Yin

Electronics 2022, 11(24), 4209; https://doi.org/10.3390/electronics11244209 - 16 Dec 2022

Viewed by 1510

Abstract

Many radar applications, such as system design and testing and target detection and recognition, need to compress and rapidly reconstruct the target-scattering characteristics data through some suitable sparse representations, while the scattering center (SC) model resulting from different scattering mechanisms is just a [...] Read more.

Many radar applications, such as system design and testing and target detection and recognition, need to compress and rapidly reconstruct the target-scattering characteristics data through some suitable sparse representations, while the scattering center (SC) model resulting from different scattering mechanisms is just a prospective candidate. For the target scattering characteristics data with single reflection/diffraction mechanisms, the multimanifold structures of wide-angle SCs were revealed in light of asymptotic high-frequency theory and ray theory of electromagnetic field. Then the multimanifold clustering and curve/surface fitting algorithms are introduced to construct the target global SC (GSC) model. Compared with simulation data of sphere-cone target, the RCS at elevation

90^{°}

, azimuth

0 - 180^{°}

can be accurately reconstructed by only 77 parameters, the compress rate and root mean square error are 0.66 and 1.17 dB respectively. Simulation results showed that the GSC model could greatly compress the wide-angle scattering data while ensuring a suitable reconstruction accuracy. The proposed multimanifold GSC representation is convenient to implement and can effectively replace the redundant original scattering characteristics data. Full article

(This article belongs to the Special Issue Recent Advancements and Applications of Computational Electromagnetics)

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12 pages, 8884 KiB

Open AccessFeature PaperArticle

Electromagnetic–Thermal Co-Simulation of Planar Monopole Antenna Based on HIE-FDTD Method

by Chunhui Mou, Juan Chen and Huaiyun Peng

Electronics 2022, 11(24), 4167; https://doi.org/10.3390/electronics11244167 - 13 Dec 2022

Cited by 2 | Viewed by 1095

Abstract

This paper presents an efficient approach to implement electromagnetic-thermal (EM-T) co-simulation of a planar monopole antenna based on hybrid implicit-explicit finite-difference time-domain method (HIE-FDTD-M). First, the EM simulation is carried out by solving Maxwell’s curl equation. Once the EM field reaches steady state, [...] Read more.

This paper presents an efficient approach to implement electromagnetic-thermal (EM-T) co-simulation of a planar monopole antenna based on hybrid implicit-explicit finite-difference time-domain method (HIE-FDTD-M). First, the EM simulation is carried out by solving Maxwell’s curl equation. Once the EM field reaches steady state, the EM power loss is computed according to the electric conductivity of the material. Finally, the thermal field is simulated by taking the EM power loss as the heat source in the heat transfer equation (HTE). For comparison, HIE-FDTD-M and FDTD-M are adopted respectively in the computation of the EM field. The simulated EM parameters of the planar monopole antenna, including S₁₁ and radiation pattern, are consistent with those obtained by using CST software. The thermal field distribution on the surface of the antenna computed by the proposed method in this paper is approximately similar to that obtained using COMSOL software. However, the EM-T co-simulation of the antenna using HIE-FDTD-M takes only 1/11 of the time required using FDTD-M. Full article

(This article belongs to the Special Issue Recent Advancements and Applications of Computational Electromagnetics)

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11 pages, 2828 KiB

Open AccessArticle

Application of Skeletonization-Based Method in Solving Inverse Scattering Problems

by Xinhui Zhang, Bingyuan Liang and Xiuzhu Ye

Electronics 2022, 11(23), 4005; https://doi.org/10.3390/electronics11234005 - 02 Dec 2022

Viewed by 1138

Abstract

In electromagnetic inverse scattering problems, Scattered field commonly needs to be measured by a large number of receiving antennas to provide enough scattered information for image reconstruction, which may increase the cost of the experimental system and require a long testing time. In [...] Read more.

In electromagnetic inverse scattering problems, Scattered field commonly needs to be measured by a large number of receiving antennas to provide enough scattered information for image reconstruction, which may increase the cost of the experimental system and require a long testing time. In this paper, a skeletonization-based method was proposed to reduce the number of actual receiving antennas involved in an inverse scattering system. The skeleton points were obtained by performing a strong-rank-revealing QR factorization of Green’s function matrix. By measuring the scattered field only at the skeleton points, the number of receiving antennas could be effectively reduced, while the scattered field data at other receiving points could be accurately restored from the skeleton points. The numerical results show that, compared with the frequency domain zero-padding (FDZP) method, the skeletonization-based method was more accurate for antennas distributed in an elliptical shape (such as thorax imaging). In addition, the inverse scattering method using the skeletonization-based method was able to reduce the number of measurements while maintaining an image quality comparable to that of the actual full measurement system. The proposed method can serve as a guidance for building an experimental system for inverse scattering problems, especially for cases when the antennas are elliptically distributed. Full article

(This article belongs to the Special Issue Recent Advancements and Applications of Computational Electromagnetics)

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15 pages, 2075 KiB

Open AccessArticle

An Adaptive Rational Fitting Technique of Sommerfeld Integrals for the Efficient MoM Analysis of Planar Structures

by Zi-Hao Zhao, Bi-Yi Wu, Ze-Lin Li, Ming-Lin Yang and Xin-Qing Sheng

Electronics 2022, 11(23), 3940; https://doi.org/10.3390/electronics11233940 - 28 Nov 2022

Cited by 2 | Viewed by 898

Abstract

The integral equation method is one of the most successful computational models for microwave devices or integrated circuits in planar layered media. However, the efficient and accurate evaluation of the associated Green’s function consisting of Sommerfeld integrals (SIs) is still a remaining challenge. [...] Read more.

The integral equation method is one of the most successful computational models for microwave devices or integrated circuits in planar layered media. However, the efficient and accurate evaluation of the associated Green’s function consisting of Sommerfeld integrals (SIs) is still a remaining challenge. To mitigate this difficulty, this work proposes a spatial domain rational function fitting technique (RFFT) for SIs so that the approximation accuracy is controllable. In conjunction with an adaptive sampling strategy, the proposed RFFT minimizes the orders of rational functions, and the resultant SI evaluation efficiency is optimized. In addition, we investigate the semi-analytical singularity treatment for the rational expression of SIs in method of moment (MoM) implementation. Extensive simulation of representative planar devices validates the correctness of the proposed method and demonstrates its superior performance over conventional SI approximation methods. Full article

(This article belongs to the Special Issue Recent Advancements and Applications of Computational Electromagnetics)

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13 pages, 3489 KiB

Open AccessArticle

Numerical Modelling of Dynamic Electromagnetic Problems Based on the Time-Domain Finite Integration Technique

by Zhuochen Lou, Xiongwei Wu, Junming Hou, Jianan Zhang, Jianwei You and Tiejun Cui

Electronics 2022, 11(23), 3912; https://doi.org/10.3390/electronics11233912 - 26 Nov 2022

Cited by 2 | Viewed by 1159

Abstract

Developing numerical methods to solve dynamic electromagnetic problems has broad application prospects. In computational electromagnetics, traditional numerical methods are commonly used to deal with static electromagnetic problems. However, they can hardly be applied in the modeling of time-varying materials and moving objects. So [...] Read more.

Developing numerical methods to solve dynamic electromagnetic problems has broad application prospects. In computational electromagnetics, traditional numerical methods are commonly used to deal with static electromagnetic problems. However, they can hardly be applied in the modeling of time-varying materials and moving objects. So far, the studies on numerical methods that can efficiently solve dynamic electromagnetic problems are still very limited. In this paper, a numerical method called the time-domain finite integration technique (TDFIT) is extended to tackle this problem via the introduction of time-varying iterative coefficients. In order to validate the effectiveness of the proposed algorithm, three numerical examples are demonstrated, including two microstrip structures with a time-varying medium and a rapidly rotating structure. The numerical results reveal that the time-varying medium can induce a nonlinear spectrum shift, and the radar cross section (RCS) of a rapidly rotating structure is highly dependent on the rotating speed. The proposed algorithm opens a new avenue for the exploration of many intriguing phenomena in fundamental physics, including frequency conversion and magnetless nonreciprocity. Meanwhile, it can also lead to a wide range of promising practical applications, such as active electron devices, space-time metamaterials, and hypersonic vehicles. Full article

(This article belongs to the Special Issue Recent Advancements and Applications of Computational Electromagnetics)

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10 pages, 2679 KiB

Open AccessFeature PaperArticle

An Efficient Volume Integral Equation Method for Analysis of Boresight Error of a Radome with Minor Ablation

by Xiao-Yang He, De-Hua Kong, Wen-Wei Zhang and Ming-Yao Xia

Electronics 2022, 11(23), 3861; https://doi.org/10.3390/electronics11233861 - 23 Nov 2022

Viewed by 1140

Abstract

In this paper, an efficient method based on volume integral equation is developed to analyze the effects of ablation of a radome on the boresight error. To avoid recalculating the whole impedance matrix when the permittivity of the radome or the shape of [...] Read more.

In this paper, an efficient method based on volume integral equation is developed to analyze the effects of ablation of a radome on the boresight error. To avoid recalculating the whole impedance matrix when the permittivity of the radome or the shape of the top portion is slightly changed due to ablation, the radome is divided into unaffected and affected parts and the volume equivalent current instead of the displacement current is used as the unknown. This permits us to reassemble rather than recalculate the impedance matrix when the ablation condition is altered. Moreover, a viable preconditioning technique is introduced and integrated with the multilevel fast multipole algorithm (MLFMA) to cope with the electrically large antenna-radome system (ARS). Simulation results are provided for the boresight error (BSE) and boresight error slope (BSES) of the ARS at some different ablation states. The present approach is considerably faster than using the conventional methods. Full article

(This article belongs to the Special Issue Recent Advancements and Applications of Computational Electromagnetics)

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12 pages, 4992 KiB

Open AccessArticle

Heterogeneous CPU-GPU Accelerated Subgridding in the FDTD Modelling of Microwave Breakdown

by Jian Feng, Kaihong Song, Ming Fang, Wei Chen, Guoda Xie, Zhixiang Huang and Xianliang Wu

Electronics 2022, 11(22), 3725; https://doi.org/10.3390/electronics11223725 - 14 Nov 2022

Viewed by 957

Abstract

Microwave breakdown is crucial to the transmission of high-power microwave (HPM) devices, where a growing number of studies have analyzed the complex interactions between electromagnetic waves and the evolving plasma from theoretical and analytical perspectives. In this paper, we propose a finite-difference time-domain [...] Read more.

Microwave breakdown is crucial to the transmission of high-power microwave (HPM) devices, where a growing number of studies have analyzed the complex interactions between electromagnetic waves and the evolving plasma from theoretical and analytical perspectives. In this paper, we propose a finite-difference time-domain (FDTD) scheme to numerically solve Maxwell’s equation, coupled with a fluid plasma equation for simulating the plasma formation during HPM air breakdown. A subgridding method is adopted to obtain accurate results with lower computational resources. Moreover, the three-dimensional subgridding Maxwell–plasma algorithm is efficiently accelerated by utilizing heterogeneous computing technique based on graphics processing units (GPUs) and multiple central processing units (CPUs), which can be applied as an efficient method for the investigation of the HPM air breakdown phenomena. Full article

(This article belongs to the Special Issue Recent Advancements and Applications of Computational Electromagnetics)

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11 pages, 10340 KiB

Open AccessFeature PaperArticle

Electromagnetic Effective-Degree-of-Freedom Limit of a MIMO System in 2-D Inhomogeneous Environment

by Shuai S. A. Yuan, Zi He, Sheng Sun, Xiaoming Chen, Chongwen Huang and Wei E. I. Sha

Electronics 2022, 11(19), 3232; https://doi.org/10.3390/electronics11193232 - 08 Oct 2022

Cited by 1 | Viewed by 2002

Abstract

Compared with a single-input-single-output (SISO) wireless communication system, the benefit of multiple-input-multiple-output (MIMO) technology originates from its extra degree of freedom (DOF), also referred to as scattering channels or spatial electromagnetic (EM) modes, brought by spatial multiplexing. When the physical sizes of transmitting [...] Read more.

Compared with a single-input-single-output (SISO) wireless communication system, the benefit of multiple-input-multiple-output (MIMO) technology originates from its extra degree of freedom (DOF), also referred to as scattering channels or spatial electromagnetic (EM) modes, brought by spatial multiplexing. When the physical sizes of transmitting and receiving arrays are fixed and there are sufficient antennas (typically with half-wavelength spacings), the DOF limit is only dependent on the propagating environment. Analytical methods can be used to estimate this limit in free space, and some approximate models are adopted in stochastic environments, such as Clarke’s model and Ray-tracing methods. However, this DOF limit in a certain inhomogeneous environment has not been well discussed with rigorous full-wave numerical methods. In this work, volume integral equation (VIE) is implemented for investigating the limit of MIMO effective degree of freedom (EDOF) in three representative two-dimensional (2-D) inhomogeneous environments. Moreover, we clarify the relation between the performance of a MIMO system and the scattering characteristics of its propagating environment. Full article

(This article belongs to the Special Issue Recent Advancements and Applications of Computational Electromagnetics)

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12 pages, 2725 KiB

Open AccessArticle

A Circuit-Based Wave Port Boundary Condition for the Nodal Discontinuous Galerkin Time-Domain Method

by Shichen Zhu, Yan Shi and Zhenguo Ban

Electronics 2022, 11(12), 1842; https://doi.org/10.3390/electronics11121842 - 09 Jun 2022

Cited by 2 | Viewed by 1481

Abstract

Waveguide-like transmission line (WLTL) structures, including rectangular waveguides, circular waveguides, and coaxial lines, have been widely used in microwave engineering. Determining how to efficiently model WLTLs has become vital for the design of various WLTL-based devices. In this paper, a circuit-based wave port [...] Read more.

Waveguide-like transmission line (WLTL) structures, including rectangular waveguides, circular waveguides, and coaxial lines, have been widely used in microwave engineering. Determining how to efficiently model WLTLs has become vital for the design of various WLTL-based devices. In this paper, a circuit-based wave port boundary condition (CWPBC) is developed and applied in the discontinuous Galerkin time-domain (DGTD) method to accurately simulate these structures for the first time. In the CWPBC, modal voltages and currents of a WLTL are defined, and circuits based on modal voltages and currents are introduced. By co-simulating the modal circuit and the WLTL modeled using the DGTD method, various modal fields can be excited in the WLTL, and at the same time, the WLTL can be terminated without reflections. No extra costs or approximations are used in the proposed CWPBC, and there is no requirement of either the extension of the computational domains widely used in perfectly matched layer (PML) termination or the longitudinal field continuity used in the reported DGTD method. The proposed method can easily obtain the postprocessing parameters, including S-parameters and port power. Numerical results, including rectangular waveguide filters, circular waveguide horns, and coaxial-fed electromagnetic bandgaps (EBG), are given to validate the effectiveness of the proposed CWPBC. Full article

(This article belongs to the Special Issue Recent Advancements and Applications of Computational Electromagnetics)

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9 pages, 3299 KiB

Open AccessArticle

High-Power Electromagnetic Pulse Effect Prediction for Vehicles Based on Convolutional Neural Network

by Le Cao, Shuai Hao, Yuan Zhao and Cheng Wang

Electronics 2022, 11(9), 1490; https://doi.org/10.3390/electronics11091490 - 06 May 2022

Viewed by 1628

Abstract

This study presents a prediction model for high-power electromagnetic pulse (HPEMP) effects on aboveground vehicles based on convolutional neural networks (CNNs). Since a vehicle is often located aboveground and is close to the air-ground_–half-space interface, the electromagnetic energy coupled into the [...] Read more.

This study presents a prediction model for high-power electromagnetic pulse (HPEMP) effects on aboveground vehicles based on convolutional neural networks (CNNs). Since a vehicle is often located aboveground and is close to the air-ground_–half-space interface, the electromagnetic energy coupled into the vehicle by the ground reflected waves cannot be ignored. Consequently, the analysis of the vehicle’s HPEMP effect is a composite electromagnetic scattering problem of the half-space and the vehicles above it, which is often analyzed using different half-space numerical methods. However, traditional numerical methods are often limited by the complexity of the actual half-space models and the high computational demands of complex targets. In this study, a prediction method is proposed based on a CNN, which can analyze the electric field and energy density under different incident conditions and half-space environments. Compared with the half-space finite-difference time-domain (FDTD) method, the accuracy of the prediction results was above 98% after completing the training of the CNN network, which proves the correctness and effectiveness of the method. In summary, the CNN prediction model in this study can provide a reference for evaluating the HPEMP effect on the target over a complex half-space medium. Full article

(This article belongs to the Special Issue Recent Advancements and Applications of Computational Electromagnetics)

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11 pages, 2474 KiB

Open AccessArticle

Modeling of Multiscale Wave Interactions Based on an Iterative Scheme of MoM-PO-EPA Algorithm

by Liangshuai Guo, Maokun Li, Shenheng Xu, Fan Yang and Jun Li

Electronics 2022, 11(7), 990; https://doi.org/10.3390/electronics11070990 - 23 Mar 2022

Cited by 1 | Viewed by 1398

Abstract

Electromagnetic modeling of multiscale wave interactions is a challenging task. This is because wave physics exhibit different characteristics at different length scales that require suitable modeling algorithms. Combining these algorithms to model multiscale wave physics requires careful design and tuning. In this study, [...] Read more.

Electromagnetic modeling of multiscale wave interactions is a challenging task. This is because wave physics exhibit different characteristics at different length scales that require suitable modeling algorithms. Combining these algorithms to model multiscale wave physics requires careful design and tuning. In this study, we investigated a hybrid algorithm based on the method of moment (MoM), iterative physical optics (IPO) approximation, and the equivalence principle algorithm (EPA). EPA modeled targets with details, MoM modeled targets with moderate scales, and IPO modeled electrically large scatterers. The virtual equivalence surfaces in EPA worked as interfaces between relatively large and small scatterers. An iterative scheme is used to solve the targets instead of a matrix equation with large dimensions. This algorithm achieved a good balance between accuracy and efficiency. Numerical examples of modeling the plane-wave scattering of multiscale targets verify its performance for 2D and 3D problems. The iterative scheme can become faster and need less memory usage when solving the multiscale scatterers. Full article

(This article belongs to the Special Issue Recent Advancements and Applications of Computational Electromagnetics)

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Review

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11 pages, 1759 KiB

Open AccessReview

A Review on Fast Direct Methods of Surface Integral Equations for Analysis of Electromagnetic Scattering from 3-D PEC Objects

by Ming Jiang, Yin Li, Lin Lei and Jun Hu

Electronics 2022, 11(22), 3753; https://doi.org/10.3390/electronics11223753 - 16 Nov 2022

Viewed by 1495

Abstract

This paper reviews a series of fast direct solution methods for electromagnetic scattering analysis, aiming to significantly alleviate the problems of slow or even non-convergence of iterative solvers and to provide a fast and robust numerical solution for integral equations. Then the advantages [...] Read more.

This paper reviews a series of fast direct solution methods for electromagnetic scattering analysis, aiming to significantly alleviate the problems of slow or even non-convergence of iterative solvers and to provide a fast and robust numerical solution for integral equations. Then the advantages and applications of fast direct solution methods and the research trends are introduced in detail. Three different main methods are discussed, namely hierarchically off-diagonal low-rank matrices (HODLR) and skeletonization direct methods based on weak and strong admissibility condition. Numerical examples of computational complexity and electromagnetic scattering analysis of jet models are presented to demonstrate the efficiency and accuracy of each approach. Finally, a brief discussion is given on the main challenges and possible strategies of fast direct solution methods which still exist. Full article

(This article belongs to the Special Issue Recent Advancements and Applications of Computational Electromagnetics)

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16 pages, 4855 KiB

Open AccessReview

Hot Carrier Injection Reliability in Nanoscale Field Effect Transistors: Modeling and Simulation Methods

by Yimin Wang, Yun Li, Yanbin Yang and Wenchao Chen

Electronics 2022, 11(21), 3601; https://doi.org/10.3390/electronics11213601 - 04 Nov 2022

Cited by 3 | Viewed by 3567

Abstract

Hot carrier injection (HCI) can generate interface traps or oxide traps mainly by dissociating the Si-H or Si-O bond, thus affecting device performances such as threshold voltage and saturation current. It is one of the most significant reliability issues for devices and circuits. [...] Read more.

Hot carrier injection (HCI) can generate interface traps or oxide traps mainly by dissociating the Si-H or Si-O bond, thus affecting device performances such as threshold voltage and saturation current. It is one of the most significant reliability issues for devices and circuits. Particularly, the increase in heat generation per unit volume due to high integration density of advanced integrated circuits leads to a severe self-heating effect (SHE) of nanoscale field effect transistors (FETs), and low thermal conductivity of materials in nanoscale FETs further aggravates the SHE. High temperature improves the HCI reliability in the conventional MOSFET with long channels in which the energy of carriers can be relaxed. However, high temperature due to severe SHE deteriorates HCI reliability in nanoscale FETs, which is a big concern in device and circuit design. In this paper, the modeling and simulation methods of HCI in FETs are reviewed. Particularly, some recently proposed HCI models with consideration of the SHE are reviewed and discussed in detail. Full article

(This article belongs to the Special Issue Recent Advancements and Applications of Computational Electromagnetics)

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