Research Trends in Breakdown Phenomena in Sub-micrometer-scale Gaps

Modern electrical equipment is under increasing pressure to be miniaturized, making advanced insulation design more critical. Sub-micrometer-scale voids within insulating materials and micron-scale gaps between electrodes act as insulation defects, and extensive research has been conducted on the associated breakdown phenomena. In such narrow gaps, conventional ionization reactions are significantly suppressed, and field electron emission from electrode surfaces becomes the dominant mechanism. This paper reviews recent progress in the study of electrical breakdown in sub-micrometer-scale gaps. In addition, it introduces effective simulation approaches that contribute to a better understanding and prediction of these phenomena.