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Controlling Catalyst Bulk Reservoir Effects for Monolayer Hexagonal Boron Nitride CVD.

ABSTRACT: Highly controlled Fe-catalyzed growth of monolayer hexagonal boron nitride (h-BN) films is demonstrated by the dissolution of nitrogen into the catalyst bulk via NH3 exposure prior to the actual growth step. This "pre-filling" of the catalyst bulk reservoir allows us to control and limit the uptake of B and N species during borazine exposure and thereby to control the incubation time and h-BN growth kinetics while also limiting the contribution of uncontrolled precipitation-driven h-BN growth during cooling. Using in situ X-ray diffraction and in situ X-ray photoelectron spectroscopy combined with systematic growth calibrations, we develop an understanding and framework for engineering the catalyst bulk reservoir to optimize the growth process, which is also relevant to other 2D materials and their heterostructures.

SUBMITTER: Caneva S

PROVIDER: S-EPMC4751513 | biostudies-literature | 2016 Feb

REPOSITORIES: biostudies-literature

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Controlling Catalyst Bulk Reservoir Effects for Monolayer Hexagonal Boron Nitride CVD.

Caneva Sabina S Weatherup Robert S RS Bayer Bernhard C BC Blume Raoul R Cabrero-Vilatela Andrea A Braeuninger-Weimer Philipp P Martin Marie-Blandine MB Wang Ruizhi R Baehtz Carsten C Schloegl Robert R Meyer Jannik C JC Hofmann Stephan S

Nano letters 20160119 2

Highly controlled Fe-catalyzed growth of monolayer hexagonal boron nitride (h-BN) films is demonstrated by the dissolution of nitrogen into the catalyst bulk via NH3 exposure prior to the actual growth step. This "pre-filling" of the catalyst bulk reservoir allows us to control and limit the uptake of B and N species during borazine exposure and thereby to control the incubation time and h-BN growth kinetics while also limiting the contribution of uncontrolled precipitation-driven h-BN growth du ...[more]

PMID: 26756610

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Single Crystalline Film of Hexagonal Boron Nitride Atomic Monolayer by Controlling Nucleation Seeds and Domains.

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