Towards barrier-free contacts to monolayer transition metal dichalcogenides

Abstract

Broken inversion symmetry and time-reversal symmetry along with large spin-orbit interactions in monolayer transition metal dichalcogenides (TMDs) make them ideal candidates for novel valleytronic applications. Although successful spin transport and detection are very crucial for spintronic/valleytronic devices, electrical spin transport and spin detection due to spin-valley polarization in TMDs is still lacking. An electrical realization of spin transport and detection in TMDs demand perpendicular magnetic anisotropic (PMA) electrodes with very small Schottky barrier height (SBH). Furthermore, formation of large SBH at the metal/TMDs interfaces limits the exploitation and integration of TMDs in spintronic/valleytronic devices. In this work, we develop ferromagnetic electrodes and integrate them in MoS2 field-effect transistors. We studied the transfer characteristics of these devices and estimated SBH. SBHs extracted in these devices were found to be very small.