Membranes based on MOVPE-grown hexagonal boron nitride

Hexagonal boron nitride (h-BN) is a two-dimensional (2D) material from the III-nitride family with a wide bandgap of about 6 eV and broad application potential, including deep-ultraviolet emission and use as a substrate for other 2D materials. Its atomically flat surface, absence of dangling bonds, and uniform dielectric properties make it an ideal insulating layer in van der Waals (vdW) heterostructures. However, current vdW stacks often rely on exfoliated flakes, limiting scalability. I will present results on the epitaxial growth of h-BN on sapphire via metalorganic vapor-phase epitaxy (MOVPE), a promising route for producing large-area layers. Next, I will show how MOVPE-grown h-BN membranes can be fabricated on germanium by light-induced etching in water. These membranes exhibit polarization-dependent Raman enhancement, influencing both h-BN and nearby 2D materials. Finally, I will discuss hydrogen-filled h-BN bubbles formed by electron beam-induced radiolysis. These bubbles retain hydrogen for weeks, pointing to future applications in hydrogen storage.