Direct Observation of Dielectric Breakdown Path at Silica/Epoxy Interface with a Micro-gap Electrode Device

Abstract

We develop a micro-gap electrode device on quartz substrate to investigate the dielectric breakdown resistance on constrained layer of silica/epoxy interface. After application of stress, the device is cut at the middle of the micro-gap by laser dicing to observe the cross-section, and the cross-section shows where the breakdown occurs in the vicinity of the silica/epoxy interface at sub-micron scale. These results give us a clue to understand the effect of nano-fillers on the dielectric breakdown of nano-composite materials.