Abstract
We show that in a low-pressure chemical vapor deposition (CVD) system, the residual oxygen and/ or air play a crucial role in the mechanism of the growth of hexagonal boron nitride (h-BN) films on Ni foil ‘enclosures’. Hexagonal-BN films grow on the Ni foil surface via the formation of an intermediate boric-oxide (BOx) phase followed by a thermal reduction of the BOx by a carbon source (either amorphous carbon powder or methane), leading to the formation of single- and bi-layer h-BN. Low energy electron microscopy (LEEM) and diffraction (LEED) were used to map the number of layers over large areas; Raman spectroscopy, time-of-flight secondary ion mass spectrometry (ToF-SIMS), x-ray photoelectron spectroscopy (XPS) and scanning tunneling microscopy (STM) were used to characterize the structure and physical quality of the ultra-thin h-BN film. The growth procedure reported here leads to a better understanding and control of the synthesis of ultra-thin h-BN films.
Original language | English |
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Article number | 025117 |
Journal | 2D Materials |
Volume | 4 |
Issue number | 2 |
DOIs | |
State | Published - Jun 2017 |
Keywords
- Carbothermal reduction
- Chemical vapor deposition
- Hexagonal boron nitride
- LEEM
- Surface oxidation