We analyze broadband electromagnetic measurements of pulse sequences occurring prior to first return strokes of negative cloud-to-ground lightning flashes. Signals generated by lightning discharges were recorded close to the thunderstorm by a magnetic field receiver and traveled up to 600km to three distant electric field receivers. We found that amplitudes of observed preliminary breakdown pul...

For integrated passive device (IPD) applications, we have successfully developed and characterized metalinsulator-metal (MIM) capacitors with 2000 Å plasma-enhanced chemical vapor deposition (PECVD) silicon nitride which are deposited with the SiH4/NH3 gas mixing rate, working pressure, and RF power of PECVD at 250oC. Five PECVD process parameters are designed to lower the refractive index and ...

A 3-terminal breakdown voltage of 2.3 kV has been achieved on an AlN/GaN heterostructure grown on silicon (111) substrate using an optimized local substrate removal. The epitaxy was grown by metal organic chemical vapor deposition with a total buffer thickness of 5.5 μm. In order to suppress the parasitic substrate conduction phenomena under high electric field, the Si substrate has been locall...

Nowadays, the most widely used insulating materials in high voltage equipment such as cables are polymeric insulations due to the numerous merits they possess with regards to electrical performance compared to paper insulations. However, electrical treeing, one of the dielectric pre-breakdown phenomena, has been considered as a major contribution to the failure of insulating polymeric materials...

Streamer discharges are a primary mode of electric breakdown in thunderstorms and high voltage technology; they are generally believed to grow along electric field lines. However, we here give experimental and numerical evidence that streamers can propagate nearly perpendicularly to the background electric field. These streamers are guided by pre-ionization that is orders of magnitude lower tha...

Due to its high greenhouse effect, the use of SF6 as main insulating gas is restricted in electric power field. Along with aim environmental protection, search for new alternative gases a lower effect and higher insulation strength has received lot attention. The properties have vital impact on performance medium-voltage distribution equipment. Firstly, based existing liquefaction temperatures ...

We introduce a theoretical model to investigate the electric breakdown of a substrate on which highly conducting particles are adsorbed and desorbed with a probability that depends on the local electric field. We find that, by tuning the relative strength q of this dependence, the breakdown can change from continuous to explosive. Precisely, in the limit in which the adsorption probability is t...