Hexagonal boron nitride encapsulation is the method of choice for protecting graphene from environmental doping and impurity scattering. It was previously demonstrated that metal-organic vapor phase epitaxy (MOVPE) grows epitaxially ordered, uniform BN layers on epigraphene (graphene grown on SiC). Due to graphene non-wetting properties, h-BN growth starts preferentially from the graphene ledges. We use this fact here to selectively promote growth of high-quality flat h-BN on epigraphene by patterning epigraphene microstructures prior to BN growth. Thin h-BN films (down to 6 nm) grown by MOVPE show smooth and pleated surface morphology on epigraphene, while crumpled BN is observed on the SiC. Cross-sectional high-resolution transmission electron microscopy images and fluorescence imaging confirm the higher BN quality grown on the epigraphene. Transport measurements reveal p-doping as expected from hydrogen intercalation of epigraphene and regions of high and low mobility. This method can be used to produce structurally uniform high-quality h-BN/epigraphene micro/nano scale heterostructure.
@article{arxiv.2409.04709,
title = {High-quality hexagonal boron nitride selectively grown on patterned epigraphene by MOVPE},
author = {Vishnu Ottapilakkal and Abhishek Juyal and Suresh Sundaram and Phuong Vuong and Collin Beck and Noel L. Dudeck and Amira Bencherif and Annick Loiseau and Frédéric Fossard and Jean-Sebastien Mérot and David Chapron and Thomas H. Kauffmann and Jean-Paul Salvestrini and Paul L. Voss and Walt A. de Heer and Claire Berger and Abdallah Ougazzaden},
journal= {arXiv preprint arXiv:2409.04709},
year = {2024}
}