Theoretical analysis of the enhanced electric field at the triple junction

Abstract

The electric-field behavior at the triple junction of metal–dielectric–vacuum is theoretically investigated. For a two-dimensional junction in which the electric-field magnitude F behaves as rν−1, ν is obtained as a function of the configuration geometry and the dielectric constant. It is found that ν varies with the dielectric portion in the field-varying region, becoming as low as 0.25 in the extreme case. The enhancement of F due to the reduction of ν is responsible for the field emission enhancement as well as the vacuum insulation breakdown at the triple junction.