Growth mechanism of hydrogen-assisted multilayer Hexagonal Boron Nitride on Cu substrate

Qing Lin XIe^1*, Wei-Yen, Woon¹

¹Department of Physic, National Central Univerity, Taoyuan, Taiwan

* Presenter:Qing Lin XIe, email:j125550323@gmail.com

Hexagonal boron nitride, as an insulator with 6.8 eV bandgap, hBN becomes a promising substrate for 2D material. Nowadays, monolayer hBN is controllable during low-pressure CVD because of its self-limited effect. But, the research of growing few layers or multilayer hBN mechanism is still lacking. Most multilayer hBN are fabricated on alloy substrates like Fe-Ne alloy. In this research, we use CVD to fabricate hBN on the copper foil and control the amount of H2 which can enhance the multilayer growing. In our system, after the annealing step, the center of copper is single crystalline. We found the coverage of multilayer hBN is higher at the upstream region on the copper with polycrystalline. This article will study the effect of growing multilayer hBN on polycrystalline copper. In our system, some multilayer hBN shows it stacked with different angles. The interlayer coupling can be measured by Raman spectrum and know the peak value and peak shift with a number of layers and the different stacking angles. The multilayer hBN distribution with different gas ratios and the effect of the grain boundary image obtain from scanning electron microscope.

Keywords: multilayer Hexagonal boron nitride, Raman spectrum, hydrogen-assisted, Cu substrate