Dielectric material for monolayer black phosphorus transistors: A first-principles investigation

Using advanced parameter-free first-principles calculations, we suggested that corundum (a-Al₂O₃) is a promising candidate of the dielectric materials for monolayer black-phosphorus (BP). Hydrogen passivated Al₂O₃ is preferred to avoid metallization with monolayer BP. Clean interface is found between monolayer BP and H-terminated Al₂O₃. The valence-band offset for these systems is around 0.9eV, which is appropriate to create a reasonable carrier injection barrier. Moreover, orientation effect is found to be of great significance for these systems. Special orientation can generate an indirect band gap for monolayer BP.