Dielectric breakdown of layered insulator

Abstract

Hexagonal boron nitride (h-BN), an insulating layered material with a wide band gap, is widely utilized as the substrate and gate insulator to achieve high carrier mobility in layered channel materials, especially graphene. However little study has been conducted on the statistical analysis of the breakdown voltages and the breakdown mechanism. Generally the dielectric breakdown of SiO2, conventional three-dimensional (3D) amorphous oxides is simply explained by a percolation model. It has not been determined whether the dielectric breakdowns of 2D layered materials follow the general breakdown phenomena for 3D amorphous oxides. In this study, the dielectric breakdown process of BN is investigated electrically and mechanically using conductive atomic force microscopy (C-AFM) and proposed a breakdown model for insulating layered material.