Insulation performance of atomic hexogonal boron nitride film under ultra-high DC electric stress

Hexagonal boron nitride (h-BN) is an ideal twodimensional dielectric material, with excellent physical, chemical, thermal, mechanical and dielectric properties, which makes it especially attractive for logic device applications. For the h-BN film used as a dielectric layer in graphene-based electronic devices, the insulation performance evaluation under ultra-high DC electric stress is a key issue. Nevertheless, only a few works can be found on the insulation performance investigation of atomic h-BN film so far. In the present work, we report on the experimental investigation of current-voltage (I-V) properties and electrical breakdown limit of the multilayer h-BN film (9nm-20nm) using electrical probing system. The I-V properties are measured, and the dielectric strength dependence on the film thickness is also measured. Results show that when the DC electric stress is applied onto the h-BN films, the I-V curves demonstrate three different stages which is independent of the thickness of the films. The breakdown thresholds are various from 0.67V/nm for 9nm to 0.96V/nm for 19nm, which exhibit high dielectric strength. Consequently, the insulation performance evaluation of atomic h-BN film could pave the way towards two-dimensional electronic device applications.