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This paper investigates the impact of negative bias temperature stress on irradiated commercial p-channel power VDMOS transistors, particularly focusing on gate oxide charge and interface trap alterations and their contribution to threshold voltage shifts. The study addresses the critical issue of transistor reliability, as threshold voltage shifts can significantly affect device performance, especially in elevated temperature and negative gate oxide field conditions. Additionally, the research explores the effects of irradiation on VDMOS power transistors, emphasizing the importance of understanding the associated electrical parameter changes. The paper presents a comprehensive analysis of static and pulsed NBT stressing, with a specific focus on novel stress signals encountered in practical applications. The experimental procedure involves irradiation and NBT stress, and the results reveal insights into the contributions of gate oxide charge and interface traps to threshold voltage shifts. The findings shed light on the reliability of electronic equipment incorporating p-channel power VDMOS transistors under various stress conditions, offering valuable insights for device design and operation.

The paper investigates temperature stability of different overvoltage protection components used in low voltage applications: transient suppresser diodes (TSD), metal-oxide varistors (MOV), gas filled surge arresters (GFSA) and polycarbon capacitors. The objective of presented research is to identify the effectiveness of the overvoltage protection as a function of temperature. Experimental results proved that GFSA have very stable operational characteristics in wide temperature range (-90/spl deg/C to +21/spl deg/C). MOV show certain improvement of their protective characteristics at elevated temperatures. Experimental results are supported by theoretical explanations.

One of the most useful applications of MOSFET semiconductor components has been introduced to improve the gamma or electron radiation detection system. In many practical cases it is not easy to carry out experimental tests of semiconductor devices in radiation environment, so it is more convenient to perform the assessment of ionizing radiation interaction with semiconductor devices by using numerical methods based on Monte Carlo simulation techniques. A large number of previous studies have mainly focused on the study of MOSFET dosimeter response to gamma and X radiation fields. Therefore, this work will be focused on a new approach to the study radiation characteristics of the MOSFET dosimeter in fields of other types, such as field of high-energy electrons (4 MeV to 20 MeV). From the engineering point of view, it is important to consider the material that is used as a physical protection of the MOSFET dosimeter. So, it is important to investigate the energy dependence of MOSFET dosimeter to different shielding materials. For this purpose, special numerical experiments of electron transport within all layers of the elementary MOSFET structure will be performed. Shielding materials such as Kovar, Titanium Alloy with Aluminum and Niobium, Titanium Alloy with Zirconium and Niobium will be considered. The electron transport will be simulated with Monte Carlo method using the software package FOTELP-2K12. The distribution of deposited energy in all material zones of interest, as well as the absorbed dose in dosimeter sensitive zone of MOSFET structure will be determined by results obtained with numerical calculations. The physical shielding factor (PSF) for the MOSFET dosimeter, which can show the correlation between dosimeter energy dependence and shielding material in the field of electron beam radiation, will be determined within the paper. After comparing values of PSF for considered materials the recommendation for a lid material that serves as shielding for MOSFE

This paper presents evolutional design of antennas for passive IC tags used at UHF-band. The shape of wire antennas is optimized using the genetic algorithm (GA) aiming at maximization of feeding power to the IC tag to lengthen the communication distance as well as minimization of the antenna size. The characteristics of the antennas printed on a dielectric substrate are evaluated using the moment method in the optimization processes. Genotypes for GA are introduced to express the shapes of lattice antennas which include loops and floating lines, and spiral antennas. It is shown that optimized antennas satisfy the required condition, and have smaller sizes in comparison with conventional meander antennas.

This paper describes deflation of finite element (FE) matrices for electromagnetic fields. The condition of the FE matrices is improved by the matrix deflation which replaces small eigenvalues with zeros. It is known that convergence of linear solvers for FE equations can be improved by using the AV method as well as explicit and implicit error correction (EC) methods which have been derived from the multigrid method. These numerical results are theorized on the basis of the matrix deflation. In particular, augmented matrices appeared in the AV and implicit EC methods are shown to have good conditioning after preconditioning. These results suggest that the above methods are based on a common mathematical principle.

Multigrid (MG) methods are known to be fast linear solvers for large-scale finite element analyses. The Gauss-Seidel method is usually adopted as the smoother for MG methods. However, recently, considerable attention has been focused on Induced Dimension Reduction (IDR)-based solvers because they are faster. In this paper, we investigate the convergence of IDR-based solvers and evaluate the performance of a MG method with an adaptive IDR-based Jacobi smoother. Numerical results show that this method has good convergence and good efficiency in parallel computations for finite element analysis of electromagnetic fields.

Multigrid (MG) methods are known to be fast linear solvers for large-scale finite element analyses. The Gauss-Seidel method is usually adopted as the smoother for MG methods. However, recently, considerable attention has been focused on Induced Dimension Reduction (IDR)-based solvers because they are faster. In this paper, we investigate the convergence of IDR-based solvers and evaluate the performance of a MG method with an adaptive IDR-based Jacobi smoother. Numerical results show that this method has good convergence and good efficiency in parallel computations for finite element analysis of electromagnetic fields.

This paper describes deflation of finite element (FE) matrices for electromagnetic fields. The condition of the FE matrices is improved by the matrix deflation which replaces small eigenvalues with zeros. It is known that convergence of linear solvers for FE equations can be improved by using the AV method as well as explicit and implicit error correction (EC) methods which have been derived from the multigrid method. These numerical results are theorized on the basis of the matrix deflation. In particular, augmented matrices appeared in the AV and implicit EC methods are shown to have good conditioning after preconditioning. These results suggest that the above methods are based on a common mathematical principle.

When visualizing a 3-D electromagnetic field analysis result, physical quantity on a surface or a cross-section of objects is visualized mostly. It is, however, desired to observe the physical quantity and the phenomenon inside the objects in 3-D space. In this paper, the method to visualize the physical quantity inside the objects with a volumetric display is proposed. The volumetric display is based on a stack of LCDs, and developed to separately display the images on the LCDs. With the volumetric display, the physical quantity, which changes on different cross-sections of the objects in 3-D, can be visualized simultaneously. The volumetric display is also used for image comparison. In order to compare the results of magnetic field analysis, usually each image is compared by overlappingly visualizing these. However, it is easy to visualize the images and compare these, using the volumetric display. The volumetric display is a useful tool for post-processing of the electromagnetic field analysis.

When visualizing a 3-D electromagnetic field analysis result, physical quantity on a surface or a cross-section of objects is visualized mostly. It is, however, desired to observe the physical quantity and the phenomenon inside the objects in 3-D space. In this paper, the method to visualize the physical quantity inside the objects with a volumetric display is proposed. The volumetric display is based on a stack of LCDs, and developed to separately display the images on the LCDs. With the volumetric display, the physical quantity, which changes on different cross-sections of the objects in 3-D, can be visualized simultaneously. The volumetric display is also used for image comparison. In order to compare the results of magnetic field analysis, usually each image is compared by overlappingly visualizing these. However, it is easy to visualize the images and compare these, using the volumetric display. The volumetric display is a useful tool for post-processing of the electromagnetic field analysis.

Multigrid (MG) methods are known to be fast linear solvers for large-scale finite element analyses. The Gauss-Seidel method is usually adopted as the smoother for MG methods. However, recently, considerable attention has been focused on Induced Dimension Reduction (IDR)-based solvers because they are faster. In this paper, we investigate the convergence of IDR-based solvers and evaluate the performance of a MG method with an adaptive IDR-based Jacobi smoother. Numerical results show that this method has good convergence and good efficiency in parallel computations for finite element analysis of electromagnetic fields.

This paper presents evolutional design of antennas for passive IC tags used at UHF-band. The shape of wire antennas is optimized using the genetic algorithm (GA) aiming at maximization of feeding power to the IC tag to lengthen the communication distance as well as minimization of the antenna size. The characteristics of the antennas printed on a dielectric substrate are evaluated using the moment method in the optimization processes. Genotypes for GA are introduced to express the shapes of lattice antennas which include loops and floating lines, and spiral antennas. It is shown that optimized antennas satisfy the required condition, and have smaller sizes in comparison with conventional meander antennas.

This paper describes deflation of finite element (FE) matrices for electromagnetic fields. The condition of the FE matrices is improved by the matrix deflation which replaces small eigenvalues with zeros. It is known that convergence of linear solvers for FE equations can be improved by using the AV method as well as explicit and implicit error correction (EC) methods which have been derived from the multigrid method. These numerical results are theorized on the basis of the matrix deflation. In particular, augmented matrices appeared in the AV and implicit EC methods are shown to have good conditioning after preconditioning. These results suggest that the above methods are based on a common mathematical principle.

When visualizing a 3-D electromagnetic field analysis result, physical quantity on a surface or a cross-section of objects is visualized mostly. It is, however, desired to observe the physical quantity and the phenomenon inside the objects in 3-D space. In this paper, the method to visualize the physical quantity inside the objects with a volumetric display is proposed. The volumetric display is based on a stack of LCDs, and developed to separately display the images on the LCDs. With the volumetric display, the physical quantity, which changes on different cross-sections of the objects in 3-D, can be visualized simultaneously. The volumetric display is also used for image comparison. In order to compare the results of magnetic field analysis, usually each image is compared by overlappingly visualizing these. However, it is easy to visualize the images and compare these, using the volumetric display. The volumetric display is a useful tool for post-processing of the electromagnetic field analysis.

This paper describes deflation of finite element (FE) matrices for electromagnetic fields. The condition of the FE matrices is improved by the matrix deflation which replaces small eigenvalues with zeros. It is known that convergence of linear solvers for FE equations can be improved by using the AV method as well as explicit and implicit error correction (EC) methods which have been derived from the multigrid method. These numerical results are theorized on the basis of the matrix deflation. In particular, augmented matrices appeared in the AV and implicit EC methods are shown to have good conditioning after preconditioning. These results suggest that the above methods are based on a common mathematical principle.

This paper presents evolutional design of antennas for passive IC tags used at UHF-band. The shape of wire antennas is optimized using the genetic algorithm (GA) aiming at maximization of feeding power to the IC tag to lengthen the communication distance as well as minimization of the antenna size. The characteristics of the antennas printed on a dielectric substrate are evaluated using the moment method in the optimization processes. Genotypes for GA are introduced to express the shapes of lattice antennas which include loops and floating lines, and spiral antennas. It is shown that optimized antennas satisfy the required condition, and have smaller sizes in comparison with conventional meander antennas.

Multigrid (MG) methods are known to be fast linear solvers for large-scale finite element analyses. The Gauss-Seidel method is usually adopted as the smoother for MG methods. However, recently, considerable attention has been focused on Induced Dimension Reduction (IDR)-based solvers because they are faster. In this paper, we investigate the convergence of IDR-based solvers and evaluate the performance of a MG method with an adaptive IDR-based Jacobi smoother. Numerical results show that this method has good convergence and good efficiency in parallel computations for finite element analysis of electromagnetic fields.

The goal of this paper is to examine and investigate comparative analysis the resistance of some commercial EPROM and EEPROM components under the influence of gamma radiation. Experimental results show that EPROM components have better radioactive reliability than EEPROM components. Also, the EPROM changes are reversible and after erasing process and reprogramming all EPROM components are functional. On the other hand EEPROM changes are irreversible and under the influence of gamma radiation all EEPROM components became permanently nonfunctional. These results are considered relevant for the use of these components in both military industry and space technology. The obtained results are analyzed and explained theoretically.

The aim of this paper is to determine how to improve the protective characteristics of gas filled surge arresters (GFSA) on the best way. In this order there were big number of examinations of construction factors influence on following GFSA characteristics: 1) static breakdown voltage, 2) dynamic breakdown voltage, 3) volt-second characteristic. Influence of radiation sources close to GFSA electrodes is one very important construction factor. In GFSA model used in this research are built in alpha (241Am) and beta(90Sr) sources, respectively. During examination due to detail analysis influence of radiation sources on GFSA characteristics were changed type of gas and gas pressure in chamber. Also, we presented an alternative method for improvement of GFSA protective characteristic without the use of radioactive sources. With the application of hollow cathode improvement of protective characteristic is obtained. On the base of experimental results we can conclude that built in radioactive sources significantly improve the protective characteristics of GFSA. This is especially obvious in decreasing of response time more then three times e.g. from 100 ns to 30 ns. On the lower pressure the alfa emitters application is more useful and on the higher pressure the beta emitters application is more useful because of the greater cross section for ionization by beta particles. Hollow cathode method is less efficient then the radioactive filling method, but also less risk for the environment. We believe that the future prospects should be to investigate the possibility of combined use of short-living radioactive isotope and hollow cathode effect. The measuring methodology was based on the computer controlled high quality instrumentation and statistics experiment organization. This approach assures the high accuracy, reliability and repeatability of performed measurement.

The paper goal is to determine usefulness of gas riled surge arresters (GFSA) with a built-in radioactive sources application in a radiation environment. Furthermore, pseudo-empiric method has ben developed lo determine GFSA pulse shape characteristic. These resulls are considered rdevanl for lhe use of this compoaenl in military applications and in spare technology.