High-quality hexagonal boron nitride selectively grown on patterned epigraphene by MOVPE

Vishnu Ottapilakkal; Abhishek Juyal; Suresh Sundaram; Phuong Vuong; Collin Beck; Noel L. Dudeck; Amira Bencherif; Annick Loiseau; Frédéric Fossard; Jean-Sebastien Mérot; David Chapron; Thomas H. Kauffmann; Jean-Paul Salvestrini; Paul L. Voss; Walt A. de Heer; Claire Berger; Abdallah Ougazzaden

arXiv · 2409.04709

High-quality hexagonal boron nitride selectively grown on patterned epigraphene by MOVPE

Vishnu Ottapilakkal·Abhishek Juyal·Suresh Sundaram·Phuong Vuong·Collin Beck·Noel L. Dudeck·Amira Bencherif·Annick Loiseau·Frédéric Fossard·Jean-Sebastien Mérot·David Chapron·Thomas H. Kauffmann·Jean-Paul Salvestrini·Paul L. Voss·Walt A. de Heer·Claire Berger·Abdallah Ougazzaden

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Abstract

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.

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Vishnu Ottapilakkal, Abhishek Juyal, Suresh Sundaram, Phuong Vuong, Collin Beck, Noel L. Dudeck, Amira Bencherif, Annick Loiseau, Frédéric Fossard, Jean-Sebastien Mérot, David Chapron, Thomas H. Kauffmann, Jean-Paul Salvestrini, Paul L. Voss, Walt A. de Heer, Claire Berger, Abdallah Ougazzaden. 2024-09-07. High-quality hexagonal boron nitride selectively grown on patterned epigraphene by MOVPE. https://arxiv.org/abs/2409.04709

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