NbS2 : A Promising p-Type Ohmic Contact for Two-Dimensional Materials

Achieving Ohmic contact for two-dimensional- (2D) based electronics is important yet challenging. Here through first-principles calculations, we predict that a NbS2 monolayer is an excellent electrode for p-type Ohmic contacts for 2D materials. Dipole analysis indicates van der Waals interfacial interaction and high electrode work function are critical for asymmetric dipole compensation to maintain the Ohmic contact for NbS2/BP and NbS2/WSe2. p-type Ohmic contacts for both heterostructures are independent of gating up to very large electric field (7 V/nm) suggesting good stability for device applications. Our work provides a practical strategy to realize stable p-type Ohmic contacts for future 2D nanoelectronics.