Monolayer MoS₂ field effect transistor with low Schottky barrier height with ferromagnetic metal contacts

Two-dimensional MoS₂ has emerged as promising material for nanoelectronics and spintronics due to its exotic properties. However, high contact resistance at metal semiconductor MoS₂ interface still remains an open issue. Here, we report electronic properties of field effect transistor devices using monolayer MoS₂ channels and permalloy (Py) as ferromagnetic (FM) metal contacts. Monolayer MoS₂ channels were directly grown on SiO₂/Si substrate via chemical vapor deposition technique. The increase in current with back gate voltage (V_g) shows the tunability of FET characteristics. The Schottky barrier height (SBH) estimated for Py/MoS₂ contacts is found to be +28.8 meV (at V_g = 0V), which is the smallest value reported so-far for any direct metal (magnetic or non-magnetic)/monolayer MoS₂ contact. With the application of positive gate voltage, SBH shows a reduction, which reveals ohmic behavior of Py/MoS₂ contacts. Low SBH with controlled ohmic nature of FM contacts is a primary requirement for MoS₂ based spintronics and therefore using directly grown MoS₂ channels in the present study can pave a path towards high performance devices for large scale applications.