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The purpose of this paper is to establish a systemic yoyo model‐based explanation for the internal structure of atoms, which is totally different of the conventional ones.

The spin fields of systemic yoyos are used to explain the interactions between electric and magnetic fields and between elementary particles.

The concepts of potential pits (traps) and ramparts for electrons and those of nuclear, atomic, and molecular bonds are introduced. These concepts are employed successfully to describe the topological structure of atoms.

Other than providing a brand new model for the internal structure of atoms, this paper establishes a deeper understanding of the general systemic yoyo mode.

The purpose of this paper is to reach two goals: one is to generalize the well‐studied theories of electricity and magnetism to the enrichment of deepened understanding of the general systemic yoyo model, and the other is to employ the established yoyo model to provide more refined explanations for some of the known experimental observations in physics.

The general structure and the field characteristics of the general systemic yoyo model are employed as the basis of our exploration in this paper. Then, methods of quantitative analysis are introduced to address some of the problems encountered.

Among several new results, many important concepts, such as ring‐shaped electric fields, cylinders of equal potential intensities, yoyo resistances, yoyo capacitors, etc. are introduced and studied in some detail. Several important Laws in electromagnetic theory, such as Ohm's law, Kirchhoff's laws, etc. are generalized to the case of the general systemic yoyo model. The refined theory is applied to provide theoretical explanations for some laboratory‐observed phenomena that cannot be well illustrated by either Faraday's theory of electromagnetic induction or Lenz's law.

Phenomena related to electricity and magnetism are explained the first time in history by using a unified model: the systemic yoyo model. At the same time, some well established Laws in physics are generalized to scenarios of this general mode with the hope that these new Laws can be applied equally well to natural and social sciences in the coming years.

The purpose of this paper is to optimize and improve a bipolar charge transport (BCT) model used to simulate charge dynamics in insulating polymer materials, specifically low-density polyethylene (LDPE).

An optimization algorithm is applied to optimize the BCT model by comparing the model outputs with experimental data obtained using two kinds of measurements: space charge distribution using the pulsed electroacoustic (PEA) method and current measurements in nonstationary conditions.

The study provides an optimal set of parameters that offers a good correlation between model outputs and several experiments conducted under varying applied fields. The study evaluates the quantity of charges remaining inside the dielectric even after 24 h of short circuit. Moreover, the effects of increasing the electric field on charge trapping and detrapping rates are addressed.

This study only examined experiments with different applied electric fields, and thus the obtained parameters may not suit the experimental outputs if the experimental temperature varies. Further improvement may be achieved by introducing additional experiments or another source of measurements.

This work provides a unique set of optimal parameters that best match both current and charge density measurements for a BCT model in LDPE and demonstrates the use of trust region reflective algorithm for parameter optimization. The study also attempts to evaluate the equations used to describe charge trapping and detrapping phenomena, providing a deeper understanding of the physics behind the model.

The present experiments are intended to help characterize defects in very thin MOS oxide and at its Si/SiO₂ interface using a temperature‐dependent electrical characterization method, high low temperature capacitance voltage method and, especially, to investigate high temperature range. Oxide‐fixed traps are differentiated from slow‐state traps and from fast‐state traps by evaluating their electrical behaviour at different temperatures. The analysis points out the excess current after Fowler Nordheim electron injection based on hole generation, trapping, and hopping transport at high temperatures. The defect relaxation property versus temperature is investigated and defect relaxation activation energies are calculated. Creation mechanisms of interface states are especially identified by injection at different temperatures and these are compared with the other two kinds of defects. Fast‐state traps and all defect cross‐sections are calculated along and their creation activation energies are determined from Arrhenius plots.

An energy‐momentum transport model for sub‐micron silicon devices is modified to include new sets of simple interband scattering models representing impact ionization, auger recombination, trapping and photo generation. These have been developed using a simplified physical modelling approach. A discretization scheme suitable for application to an irregular spatial grid is presented. The resulting model is suitable for the study of small geometry effects in silicon devices.

As the physical dimensions of the devices are reduced to the submicrometer regime, the hot‐carrier reliability has become an important issue in the scaling of the p‐MOSFET as well as the n‐MOSFET. In this paper, we present a unified approach for p‐MOSFET degradation due to the trapping of the hot electrons in the gate oxide layers. A physical analytical model, based on the pseudo two‐dimensional model, is derived for the first time to describe the linear and saturation drain current degradation. The model has been verified by comparing the calculation and the measurement from submicron p‐MOSFET's with different channel lengths and oxide thickness. There are no empirical parameters in the model. Two physical parameters: the capture cross section and the density of states of electron traps, which can be determined independently from the measured degradation characteristics, are valid for both the linear current and the saturation current degradation. The simple expression is very suitable for the predicting of the circuit reliability.

The purpose of this paper is numerical calculation of total electric field in oil-paper insulation. Now, there is no effective method to consider the influence of space charges when calculating the total electric field distribution in the main insulation system of the valve-side winding of an ultra-high-voltage direct current converter transformer.

To calculate the total electric field in an oil-paper insulation system, a new simulation method in single-layer oil-paper insulation based on the transient upstream finite element method (TUFEM) is proposed, in which the time variable is considered. The TUFEM is used to calculate the total electric field in an oil-paper insulation system by considering the move law of space charges. The simulation method is verified by comparing the simulation results to the test data. The move law of space charges and distribution characteristics of the electric field under difference voltage values in single-layer oil-paper insulation were presented.

The results show that the TUFEM has an excellent accuracy compared with the test data. When carrier mobility is a constant, the time to reach the steady state is inversely correlated with the initial electric field intensity, and the distortion rate of the internal total electric field is positively correlated with the initial electric field intensity.

This paper provides an exploratory research on the simulation of space charge transport phenomenon in oil-paper and has guiding significance to the design of oil-paper insulation.

The purpose of this paper is to explore and develop specific models of the kinetics of isothermal depolarization currents (IDC) and the corresponding methods for the diagnostics of the physical parameters of localized electronic states (LES) in heterogeneous materials and corresponding polycrystalline semiconductor materials and heterogeneous insulators with a conductive phase.

Analysis of the kinetics of isothermal depolarization on the basis of the models allowed the authors to establish a sufficient level of their information content. This also allowed the possibility of applying for research and testing of heterogeneous structures of electronic technique.

Optimal conditions (full charge of LES on one side of the object and full discharge on the other side) and the correction factors, allowed the researchers to find concentration of these states using the developed models.

This paper uses a particular method to determine and test the parameters of LES, including operations of determining the time constant of IDC signal from its frequency spectrum, finding the ionization energy and the capture coefficient of electrons from the temperature dependence of this time constant, determining the concentration based on the integration of the time dependence of current density of IDC in the time interval that boundaries are determined from the limited range of frequencies of the signal IDC spectrum has been proposed, validated and verified by numerical experiments.

The purpose of this study is to numerically examine the heat transfer and transport of space charges in the solid insulating materials [low density polyethylene (LDPE), flame retardant type 4 (FR4), Polytetrafluoroethylene (PTFE)] using the transmission line modeling (TLM) method. Besides, a comprehensive study is performed on the mutual influences of heat transfer and space charges transport within the solid dielectric bulk.

The obtained governing equations including continuity and circuit equations are coupled with heat transfer equations, and they are solved via fourth-order Runge–Kutta method.

The electric potential and field, current density and temperature distribution are calculated. It is shown that compared with FR4 and PTFE, the temperature increment rate in LDPE is much lower. Moreover, the heat transfer in the solid insulating materials bulk increases the homo-charges density and temperature in the vicinity of electrodes. Hence, the reduction in electric field is reflected in the potential deformations in the proximity of electrodes. Furthermore, where the electric field is maximized, the temperature is minimized.

This study is restricted to two-dimensional problems.

Interestingly, because of the lower temperature in LDPE, the current density and their increment rates in LDPE are much lower than that in FR4 and PTFE dielectric materials.

High‐dielectric thin films are considered as future dielectric for Si based advanced integrated circuit technology and also for the development of organic thin film transistors and micro sensors. The conventional dielectric SiO₂ is grown by thermal oxidation of silicon whereas the HfO₂ films are grown by both physical and chemical methods. Depending on film deposition technique, the film and interface characteristics are affected. The purpose of this paper is to investigate the effect of thermal annealing in oxygen and nitrogen ambient on the electrical properties of HfO₂‐based metal oxide semiconductor (MOS) capacitor and evaluate thermal stability of the characteristics.

HfO₂ films are deposited by rf sputtering and Al‐HfO₂‐Si MOS capacitor fabricated. The electrical I‐V and C‐V characteristics are measured and the effect of temperature in the range of 25‐200°C is evaluated for films annealed in oxygen and nitrogen.

It is found that thermal annealing in nitrogen reduces oxide trap density and improves the temperature stability compared to the film annealed in oxygen for MOS devices. From the conductance characteristics D_it oxide trap density in the film is estimated to be 2.1×10¹¹/cm² for nitrogen and 3.23×10¹¹/cm² for oxygen, which indicates the role of nitrogen in reducing oxide traps. The thermal activation energy of electron traps is found to be about 0.19 eV for nitrogen and 0.58 eV for oxygen annealed films in the temperature range of 25‐150°C.

The paper examines and compares the role and effect of thermal annealing in nitrogen ambient and oxygen ambient on the electrical properties of sputtered HfO₂ thin film for improved MOS device reliability.