Anisotropic Dielectric Breakdown Strength of Single Crystal Hexagonal Boron Nitride
arXiv:1610.09842 · doi:10.1021/acsami.6b06425
Abstract
Dielectric breakdown has historically been of great interest from the perspectives of fundamental physics and electrical reliability. However, to date, the anisotropy in the dielectric breakdown has not been discussed. Here, we report an anisotropic dielectric breakdown strength (EBD) for h-BN, which is used as an ideal substrate for two-dimensional (2D) material devices. Under a well-controlled relative humidity, EBD values in the directions both normal and parallel to the c axis (EBD+c & EBD//c) were measured to be 3 and 12 MV/cm, respectively. When the crystal structure is changed from sp3 of cubic-BN (c-BN) to sp2 of h-BN, EBD+c for h-BN becomes smaller than that for c-BN, while EBD//c for h-BN drastically increases. Therefore, h-BN can possess a relatively high EBD concentrated only in the direction parallel to the c axis by conceding a weak bonding direction in the highly anisotropic crystal structure. This explains why the EBD//c for h-BN is higher than that for diamond. Moreover, the presented EBD value obtained from the high quality bulk h-BN crystal can be regarded as the standard for qualifying the crystallinity of h-BN layers grown via chemical vapor deposition for future electronic applications.
References in corpus (7)
- Boron nitride substrates for high-quality graphene electronics
- Intrinsic and Extrinsic Performance Limits of Graphene Devices on SiO2
- Atomically thin boron nitride: a tunnelling barrier for graphene devices
- Accessing the transport properties of pristine few-layer black phosphorus by van der Waals passivation in inert atmosphere
- Substrate limited electron dynamics in graphene
- Dielectric Screening in Atomically Thin Boron Nitride Nanosheets
- High-Quality BN-Graphene-BN Nanoribbon Capacitors Modulated by Graphene Side-gate Electrodes