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Partial Discharges (PD) in cavities are responsible for the greatest ageing rate in polymeric solid dielectrics due to chemical and physical deterioration mechanisms activated by the charge carriers, Ultra Violet (UV) radiation and local temperature rising during PDs activity. From the above, it is necessary to develop prognosis tools based on PDs measurements as diagnostic quantities in order to infer the time-to-breakdown, life, of solid dielectrics for improving the reliability of electrical assets, especially in current applications where they are subject to great electrical stresses in voltage frequency and magnitude. In this paper, the degradation in polymeric materials induced by PDs in cavities is briefly discussed from a phenomenological point of view, and then it is quantitatively evaluated using a simulation-based approach and a new proposed damage function. The time-to-breakdown calculated from simulations exhibits good agreement when compared with experimental measurements. Additionally, an analysis on the effect of the magnitude and frequency of the applied voltage on the degradation rate is also presented and the effectiveness of a degradation indicator, proposed by other authors, is evaluated under different stress conditions.

A simply curved Weibull plot means that the studied data set has a three-parameter Weibull distribution with a non-zero location parameter representing the lower or the upper limit of the data set. This paper introduces a four-parameter Weibull distribution with both of these limits that can be applied in both reliability and materials engineering. A very reliable indicator of this distribution is the double-curved Weibull plot. The great advantage of this distribution is the fact that the corresponding hazard rate curve can be bathtub-shaped with a great ability to fit the measured data.

Results of investigation into the effect of the processing method on the treeing resistance of polystyrene, polymethylmethacrilate, and polycarbonate are presented. It is demonstrated that in the presence of residual internal strain arising at the stage of processing, the highest treeing resistance possess polymers with a higher tensile yield strength. The tree propagation rate can be decreased and the time to breakdown of polymeric dielectrics can be increased by decreasing the thermal diffusivity of the base polymers.

Miniaturization in integrated circuits requires that the Cu diffusion barriers located in interconnects between the Cu metal line and the dielectric material should scale down. Replacing the conventional TaN with a 2D transition metal dichalcogenide barrier potentially offers the opportunity to scale to 1–2 nm thick barriers. In this article, it is demonstrated that MoS2 synthesized by atomic layer deposition (ALD) can be employed as a Cu diffusion barrier. ALD offers a controlled growth process at back‐end‐of‐line (BEOL) compatible temperatures. MoS2 films of different thicknesses (i.e., 2.2, 4.3, and 6.5 nm) are tested by time‐dependent dielectric breakdown (TDDB) measurements, demonstrating that ALD‐grown MoS2 can enhance dielectric lifetime by a factor up to 17 at an electric field of 7 MV cm−1. Extrapolation to lower E‐fields shows that the MoS2 barriers prepared by ALD have at least an order of magnitude higher median‐time‐to‐failure during device operation at 0.5 MV cm−1 compared with MoS2 barriers prepared by other methods. By scaling the thickness further down in future work, the ALD MoS2 films can be applied as ultrathin Cu diffusion barriers. MoS2 films prepared by atomic layer deposition (ALD) can potentially be applied as Cu diffusion barrier. Time‐dependent dielectric breakdown measurements show that MoS2 films effectively block Cu diffusion. ALD‐MoS2 films have at least an order of magnitude higher median‐time‐to‐failure at the device operation E‐field of 0.5 MV cm−1 than MoS2 prepared by other methods.

In this paper, long-time behaviours of classical solutions to relativistic Euler–Poisson equations in radial symmetry (REPE) are investigated. First, we establish the finite propagation speed property of the REPE system and the propagation speed σ is found to be σ : = 8 π M R ( 1 + e / c 2 ) + c 2 , where all constants are given parameters or initial data to the system. Subsequently, we show that if the initial functional ∫ 0 R v ( 0 , r ) d r is sufficiently large, then the classical solutions of the REPE will blow up on finite time, where v (0,  r ) is the initial velocity component of REPE and R is the radius of support of the initial mass-energy density.

The surface state of polymer films has a significant influence on direct current (DC) breakdown characteristics, but its mechanism needs further investigation. In this paper, DC breakdown strength of thermally aged two-layer polyester films is studied. The charge trap and their space distribution characteristics are analyzed by an isothermal relaxation current and the pulsed electro-acoustic method. Furthermore, a bipolar charge transport model suitable for two-layer dielectrics is established, and the correlation between surface state and DC breakdown performance is dynamically simulated. The experimental results show that as the aging time increases, DC breakdown strength first increases and then decreases. The trap depth and its density first increase and then decrease, and the change mainly comes from dielectric surface area. The simulation results show that through modulating the injection and accumulation behaviors of space charges, the change of trap depth, density and extended depth of surface state have an important effect on the space charge and electric field distribution at the pre-breakdown time.

The rapid and precise element measurement of trace species, such as mercury, iodine, strontium, cesium, etc. is imperative for various applications, especially for industrial needs. The elements mercury and iodine were measured by two detection methods for comparison of the corresponding detection features. A laser beam was focused to induce plasma. Emission and ion signals were detected using laser-induced breakdown spectroscopy (LIBS) and laser breakdown time-of-flight mass spectrometry (LB-TOFMS). Multi-photon ionization and electron impact ionization in the plasma generation process can be controlled by the pressure and pulse width. The effect of electron impact ionization on continuum emission, coexisting molecular and atomic emissions became weakened in low pressure condition. When the pressure was less than 1 Pa, the plasma was induced by laser dissociation and multi-photon ionization in LB-TOFMS. According to the experimental results, the detection limits of mercury and iodine in N2 were 3.5 ppb and 60 ppb using low pressure LIBS. The mercury and iodine detection limits using LB-TOFMS were 1.2 ppb and 9.0 ppb, which were enhanced due to different detection features. The detection systems of LIBS and LB-TOFMS can be selected depending on the condition of each application.

This work deals with the influence of the parameters of the working fluid (hydrostatic pressure, temperature, specific electrical conductivity) and the geometry of the electrode system (the length of the interelectrode gap and the uninsulated part of the anode) on the prebreakdown characteristics of an electric discharge in a liquid aqueous electrolyte (breakdown voltage and breakdown delay time) and the minimum charging voltage, which provides a stable high-voltage breakdown of the interelectrode gap. The research has shown that an increase in the hydrostatic pressure leads to an increase in most of the characteristics under study. At the same time, an increase in the specific electrical conductivity and temperature was observed to lead to their decrease. It was suggested that the effect of temperature on the prebreakdown characteristics is associated with a change in the specific electrical conductivity of the working fluid during its heating. The data obtained showed no effect of the length of the interelectrode gap on the breakdown voltage and its breakdown delay time as well as the minimum charging voltage. The results of the experimental studies made it possible to develop a criterion for determining the charging voltage that provides a stable high-voltage breakdown of the water interelectrode gap. Its experimental verification has shown that it can be applied to the design of electric discharge equipment and to the choice of technological modes of operation in the specified range of parameters.

In this work, we investigated the oxide reliability of 4H-SiC (0001) MOS capacitors, the oxide was fabricated about 60 nm by thermal oxidation temperature at 1350°C, the oxides than annealed at different temperatures and times in diluted NO (10% in N2). The 4H-SiC MOS structure was analyzed by C-V and I-V measurement. Compared the J-E curves and Weibull distribution curves of charge-to-breakdown for fives samples under different annealing temperature and time, it shows that the high annealing temperature improves the electrical properties as the lifetime enhanced. The mode value of field-to-breakdown (EBD) for thermal oxides by post-oxide-annealing in NO for 30 min at 1350°C was 10.09 MV/cm, the charge-to-breakdown (QBD) of this sample was the highest in all samples, and the QBD value at 63.2% cumulative failure rate was 0.15 C/cm2. The QBD of the sample annealing at 1200°C for 120 min was 0.06 C/ cm2. The effects of NO annealing in high temperature enhance the lifetime of electrical properties and field-to-breakdown obviously. It can be demonstrated that the annealing temperature as high as 1300°C for 30 min can be used to accelerate TDDB of SiC MOS gate oxide.

In this study, the reliability characteristics of metal-insulator-semiconductor (MIS) capacitor structures with low-dielectric-constant (low-k) materials have been investigated in terms of metal gate area and geometry and thickness of dielectric film effects. Two low-k materials, dense and porous low-k films, were used. Experimental results indicated that the porous low-k films had shorter breakdown times, lower Weibull slope parameters and electric field acceleration factors, and weaker thickness-dependence breakdowns compared to the dense low-k films. Additionally, a larger derivation in dielectric breakdown projection model and a single Weilbull plot of the breakdown time distributions from various areas merging was observed. This study also pointed out that the porous low-k film in the irregular-shaped metal gate MIS capacitor had a larger dielectric breakdown time than that in the square- and circle-shaped samples, which violates the trend of the sustained electric field. As a result, another breakdown mechanism exists in the irregular-shaped sample, which is required to explore in the future work.