Simple Chemical Trick Transforms Aluminum Nitride Into Tunable Semiconductor
Researchers found that adding hydrogen and fluorine atoms to ultrathin aluminum nitride sheets dramatically alters their electrical properties—turning them from metallic to semiconducting to insulating on demand. The discovery could accelerate development of next-generation electronics and magnetic devices by making aluminum nitride a practical alternative to graphene and boron nitride.
Originaltitel: On Decorating a Honeycomb AlN Monolayer with Hydrogen and Fluorine Atoms: Ab Initio and Experimental Aspects
<p>Mono- and few-layer hexagonal AlN (h-AlN) has emerged as an alternative "beyond graphene" and "beyond h-BN" 2D material, especially in the context of its verification in ultra-high vacuum Scanning Tunneling Microscopy and Molecular-beam Epitaxy (MBE) experiments. However, graphitic-like AlN has only been recently obtained using a scalable and semiconductor-technology-related synthesis techniques, such as metal-organic chemical vapor deposition (MOCVD), which involves a hydrogen-rich environment. Motivated by these recent experimental findings, in the present work, we carried out ab initio calculations to investigate the hydrogenation of h-AlN monolayers in a variety of functionalization configurations. We also investigated the fluorination of h-AlN monolayers in different decoration configurations. We find that a remarkable span of bandgap variation in h-AlN, from metallic properties to nar-row-bandgap semiconductor, and to wide-bandgap semiconductor can be achieved by its hy-drogenation and fluorination. Exciting application prospects may also arise from the findings that H and F decoration of h-AlN can render some such configurations magnetic. We complemented this modelling picture by disclosing a viable experimental strategy for the fluorination of h-AlN.</p>