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arXiv · 2206.10247

2D graphitic-like gallium nitride and structural selectivity in confinement at graphene/SiC interface

Gianfranco Sfuncia·Giuseppe Nicotra·Filippo Giannazzo·Béla Pécz·Gueorgui Kostov Gueorguiev·Anelia Kakanakova-Georgieva
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Abstract

Predictive first-principles calculations suggest graphitic-like GaN to be theoretically possible. Thus far, it has not been experimentally reported. We report on GaN monolayer in a buckled geometry obtained in confinement at graphene/SiC interface by metalorganic chemical vapor deposition (MOCVD). Conductive atomic force microscopy (C-AFM) has been employed to probe vertical current injection through the graphene/SiC interface and to establish the uniformity of the intercalated areas. Scanning transmission electron microscopy (S/TEM) has been employed for atomic resolution imaging and spectroscopy. Discontinuity in the anticipated stacking sequence of graphitic-like GaN monolayers has been exposed and reasoned as a case of simultaneous formation of Ga-N and Ga-O bonds. The formation of Ga-O bonds acquires importance in instigating chemical-species-specific structural selectivity in confinement at atom-size scale.

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Gianfranco Sfuncia, Giuseppe Nicotra, Filippo Giannazzo, Béla Pécz, Gueorgui Kostov Gueorguiev, Anelia Kakanakova-Georgieva. 2022-06-21. 2D graphitic-like gallium nitride and structural selectivity in confinement at graphene/SiC interface. https://arxiv.org/abs/2206.10247

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