Introducing Overlapping Grain Boundaries in Chemical Vapor Deposited Hexagonal Boron Nitride Monolayer Films

Autor(en)

Bernhard C, Bayer, Sabina Caneva, Timothy J. Pennycook, Jani Kotakoski, Clemens Mangler, Stephan Hofmann, Jannik C. Meyer

Abstrakt

We demonstrate the growth of overlapping grain boundaries in continuous, polycrystalline hexagonal boron nitride (h-BN) monolayer films via scalable catalytic chemical vapor deposition. Unlike the commonly reported atomically stitched grain boundaries, these overlapping grain boundaries do not consist of defect lines within the monolayer films but are composed of self-sealing bilayer regions of limited width. We characterize this overlapping hBN grain boundary structure in detail by complementary (scanning) transmission electron microscopy techniques and propose a catalytic growth mechanism linked to the subsurface/bulk of the process catalyst and its boron and nitrogen solubilities. Our data suggest that the overlapping grain boundaries are comparatively resilient against deleterious pinhole formation associated with grain boundary defect lines and thus may reduce detrimental breakdown effects when polycrystalline h-BN monolayer films are used as ultrathin dielectrics, barrier layers, or separation membranes.

Organisation(en)

Physik Nanostrukturierter Materialien

Externe Organisation(en)

University of Cambridge

Journal

ACS Nano

Band

11

Seiten

4521-4527

Anzahl der Seiten

7

ISSN

1936-0851

DOI

https://doi.org/10.1021/acsnano.6b08315

Publikationsdatum

05-2017

Peer-reviewed

Ja

ÖFOS 2012

103042 Elektronenmikroskopie, 103018 Materialphysik

Schlagwörter

ASJC Scopus Sachgebiete

Allgemeiner Maschinenbau, Allgemeine Physik und Astronomie, Allgemeine Materialwissenschaften

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/c22ff788-1701-45b3-86f8-915a1a16c5dd