Tuning the Schottky barrier height of the Pd-MoS2 contact by different strains.

Abstract

The structures and electronic properties of the Pd-MoS2 contact are investigated using density functional calculations under different strains. The height of Schottky barrier for the Pd-MoS2 contact can be tuned by different strains. Our results show that the contact nature is of n-type Schottky barrier and the barrier height can be decreased to zero under increased tensile strain (6%). However, under increased compressive strain, the MoS2 layers become indirect bandgap semiconductors, which is a disadvantage for the electron transition in the Pd-MoS2 interface. By analyzing the near band gaps and charge distribution of MoS2 orbitals, we find that the Schottky barrier height is determined by the Mo dz(2) orbitals in the Pd-MoS2 contact. Our calculation results may prove to be instrumental in future design and fabrication of MoS2-based field effect transistors.