Oxygen activated CVD growth of large-area multilayer h-BN on polycrystalline copper foils

Abstract

The synthesis of large-area multilayer hexagonal boron nitride (h-BN) is a prerequisite for advanced 2D material-based transparent electronics. The formation of large-area h-BN domains limits the possibility of grain boundary leakage current and mechanical ruptures of h-BN layers. In this work, we report the oxygen-activated synthesis of high-quality multilayer h-BN on polycrystalline copper foils, to reduce the nucleation site density and enhance the size of h-BN domains up to ∼180 μm. The oxygen-activated synthesized h-BN domains are at least 20–30 times larger than the domains synthesized by the non-oxygen-based synthesis process.Experimental results demonstrate that the h-BN domain size does not depend on the crystal orientation of the catalyst. X-ray photoelectron spectroscopy (XPS), Scanning electron microscopy (SEM), Atomic force microscopy (AFM), and Angle-resolved photoemission spectroscopy (μ-ARPES) measurements together with Raman spectroscopy indicate that the synthesized h-BN layers are of high quality.