Investigation of Nitridation on the Band Alignment at MoS2/HfO2 Interfaces

Abstract

The effect of nitridation treatment on the band alignment between few-layer MoS₂ and HfO₂ has been investigated by X-ray photoelectron spectroscopy. The valence (conduction) band offsets of MoS₂/HfO₂ with and without nitridation treatment were determined to be 2.09 ± 0.1 (2.41 ± 0.1) and 2.34 ± 0.1 (2.16 ± 0.1) eV, respectively. The tunable band alignment could be attributed to the Mo-N bonding formation and surface band bending for HfO₂ triggered by nitridation. This study on the energy band engineering of MoS₂/HfO₂ heterojunctions may also be extended to other high-k dielectrics for integrating with two-dimensional materials to design and optimize their electronic devices.